Nonmetal

This article is about the chemical elements that are not metals. For other meanings, see Nonmetal (disambiguation).

A periodic table extract highlighting nonmetals
alt=A 10x7 grid, headlined "Nonmetals in their periodic table context". ¶ The 10 columns are labeled as groups "1", "2", "3–11", and then "12" to "18". The 7 rows are left unlabeled. ¶ Most cells represent one chemical element and are labeled with its 1 or 2 letter symbol in a large font above its name. Cells in column 3 (labeled "3–11") represent a series of elements and are labeled with the first and last element's symbol. ¶ Row 1 has cells in the first and last columns, with an empty gap between. Rows 2 and 3 each have 8 cells, with a gap between the first 2 and last 6 columns. Rows 4–7 have cells in all 10 columns. ¶ 17 tan-colored cells are mostly in the top right corner: both cells row 1 and the rightmost 5/4/3/2/1 cells in rows 2–6. ¶ 6 gray-colored cells are in a falling diagonal just left of the tan cells: 1/1/2/2 cells in rows 2–5. ¶ The remaining cells have light gray letters on a white background. Most have no border, but 4 have a dashed border, one in row 6 and 3 scattered in row 7.
  always/usually considered nonmetals[1][2][3]
  metalloids, sometimes considered nonmetals[a]
  status as nonmetal or metal unconfirmed[5]
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In the context of the periodic table a nonmetal is a chemical element that mostly lacks distinctive metallic properties. They range from colorless gases like hydrogen to shiny crystals like iodine. Physically, they are usually lighter (less dense) than elements that form metals and are often poor conductors of heat and electricity. Chemically, nonmetals have relatively high electronegativity or usually attract electrons in a chemical bond with another element, and their oxides tend to be acidic.

Seventeen elements are widely recognized as nonmetals. Additionally, some or all of six borderline elements (metalloids) are sometimes counted as nonmetals.

The two lightest nonmetals, hydrogen and helium, together make up about 98% of the mass of the observable universe. Five nonmetallic elements—hydrogen, carbon, nitrogen, oxygen, and silicon—make up the bulk of Earth's atmosphere, biosphere, crust and oceans.

Industrial uses of nonmetals include in electronics, energy storage, agriculture, and chemical production.

Most nonmetallic elements were identified in the 18th and 19th centuries. While a distinction between metals and other minerals had existed since antiquity, a basic classification of chemical elements as metallic or nonmetallic emerged only in the late 18th century. Since then about twenty properties have been suggested as criteria for distinguishing nonmetals from metals.

Definition and applicable elements

[edit]
Unless otherwise noted, this article describes the stable form of an element at standard temperature and pressure (STP).[b]
Two dull silver clusters of crystalline shards.
While arsenic (here sealed in a container to prevent tarnishing) has a shiny appearance and is a reasonable conductor of heat and electricity, it is soft and brittle and its chemistry is predominately nonmetallic.[7]

Nonmetallic chemical elements are often described as lacking properties common to metals, namely shininess, pliability, good thermal and electrical conductivity, and a general capacity to form basic oxides.[8][9] There is no widely accepted precise definition;[10] any list of nonmetals is open to debate and revision.[1] The elements included depend on the properties regarded as most representative of nonmetallic or metallic character.

Fourteen elements are almost always recognized as nonmetals:[1][2]

Three more are commonly classed as nonmetals, but some sources list them as "metalloids",[3] a term which refers to elements regarded as intermediate between metals and nonmetals:[11]

One or more of the six elements most commonly recognized as metalloids are sometimes instead counted as nonmetals:

About 15–20% of the 118 known elements[12] are thus classified as nonmetals.[c]

General properties

[edit]

Physical

[edit]
See also § Physical properties by element type
Variety in color and form
of some nonmetallic elements
Several dozen small angular stone like shapes, grey with scattered silver flecks and highlights.
Boron in its β-rhombohedral phase
A shiny grey-black cuboid nugget with a rough surface.
Metallic appearance of carbon as graphite
A pale blue liquid in a clear beaker
Blue color of liquid oxygen
A glass tube, is inside a larger glass tube, has some clear yellow liquid in it
Pale yellow liquid fluorine in a cryogenic bath
Yellow powdery chunks
Sulfur as yellow chunks
A small capped jar a quarter filled with a very dark liquid
Liquid bromine at room temperature
Shiny violet-black colored crystalline shards.
Metallic appearance of iodine under white light
A partly filled ampoule containing a colorless liquid
Liquefied xenon

Nonmetals vary greatly in appearance, being colorless, colored or shiny. For the colorless nonmetals (hydrogen, nitrogen, oxygen, and the noble gases), no absorption of light happens in the visible part of the spectrum, and all visible light is transmitted.[15] The colored nonmetals (sulfur, fluorine, chlorine, bromine) absorb some colors (wavelengths) and transmit the complementary or opposite colors. For example, chlorine's "familiar yellow-green colour ... is due to a broad region of absorption in the violet and blue regions of the spectrum".[16][d] The shininess of boron, graphite (carbon), silicon, black phosphorus, germanium, arsenic, selenium, antimony, tellurium, and iodine[e] is a result of varying degrees of metallic conduction where the electrons can reflect incoming visible light.[19]

About half of nonmetallic elements are gases under standard temperature and pressure; most of the rest are solids. Bromine, the only liquid, is usually topped by a layer of its reddish-brown fumes. The gaseous and liquid nonmetals have very low densities, melting and boiling points, and are poor conductors of heat and electricity.[20] The solid nonmetals have low densities and low mechanical strength (being either hard and brittle, or soft and crumbly),[21] and a wide range of electrical conductivity.[f]

This diversity in form stems from variability in internal structures and bonding arrangements. Covalent nonmetals existing as discrete atoms like xenon, or as small molecules, such as oxygen, sulfur, and bromine, have low melting and boiling points; many are gases at room temperature, as they are held together by weak London dispersion forces acting between their atoms or molecules, although the molecules themselves have strong covalent bonds.[25] In contrast, nonmetals that form extended structures, such as long chains of selenium atoms,[26] sheets of carbon atoms in graphite,[27] or three-dimensional lattices of silicon atoms[28] have higher melting and boiling points, and are all solids, as it takes more energy to overcome their stronger bonding.[29][dubious – discuss] Nonmetals closer to the left or bottom of the periodic table (and so closer to the metals) often have metallic interactions between their molecules, chains, or layers; this occurs in boron,[30] carbon,[31] phosphorus,[32] arsenic,[33] selenium,[34] antimony,[35] tellurium[36] and iodine.[37]

Some general physical differences
between elemental metals and nonmetals[20]
Aspect Metals Nonmetals
Appearance
and form 		Shiny if freshly prepared
or fractured; few colored;[38]
all but one solid[39] 		Shiny, colored or
transparent;[40] all but
one solid or gaseous[39]
Density Often higher Often lower
Plasticity Mostly malleable
and ductile 		Often brittle solids
Electrical
conductivity[41] 		Good Poor to good
Electronic
structure[42] 		Metal or semimetalic Semimetal,
semiconductor,
or insulator

Covalently bonded nonmetals often share only the electrons required to achieve a noble gas electron configuration.[43] For example, nitrogen forms diatomic molecules featuring a triple bonds between each atom, both of which thereby attain the configuration of the noble gas neon. Antimony's larger atomic size prevents triple bonding, resulting in buckled layers in which each antimony atom is singly bonded with three other nearby atoms.[44]

Good electrical conductivity occurs when there is metallic bonding,[45] however the electrons in nonmetals are often not metallic.[45] Good electrical and thermal conductivity associated with metallic electrons is seen in carbon (as graphite, along its planes), arsenic, and antimony.[g] Good thermal conductivity occurs in boron, silicon, phosphorus, and germanium;[22] such conductivity is transmitted though vibrations of the crystalline lattices of these elements.[46] Moderate electrical conductivity is observed in the semiconductors[47] boron, silicon, phosphorus, germanium, selenium, tellurium, and iodine.

Many of the nonmetallic elements are hard and brittle,[21] where dislocations cannot readily move so they tend to undergo brittle fracture rather than deforming.[48] Some do deform such as white phosphorus (soft as wax, pliable and can be cut with a knife, at room temperature),[49] in plastic sulfur,[50] and in selenium which can be drawn into wires from its molten state.[51] Graphite is a standard solid lubricant where dislocations move very easily in the basal planes.[52]

Allotropes

[edit]
Three allotropes of carbon
A clear triangular crystal with a flat face and slightly rough edges
a transparent electrical insulator
a haphazard aggregate of brownish crystals
a brownish semiconductor
A black multi-layered lozenge-shaped rock
a blackish conductor
Diamond, buckminsterfullerene, and graphite
For a more comprehensive list, see Allotropy § Non-metals, and Single-layer materials.

Over half of the nonmetallic elements exhibit a range of less stable allotropic forms, each with distinct physical properties.[53] For example, carbon, the most stable form of which is graphite, can manifest as diamond, buckminsterfullerene,[54] amorphous[55] and paracrystalline[56] variations. Allotropes also occur for nitrogen, oxygen, phosphorus, sulfur, selenium and iodine.[57]

Chemical

[edit]
See also § Chemical properties by element type
Some general chemistry-based
differences between metals and nonmetals[20]
Aspect Metals Nonmetals
Reactivity[58] Wide range: very reactive to noble
Oxides lower Basic Acidic; never basic[59]
higher Increasingly acidic
Compounds
with metals[60] 		Alloys Ionic compounds
Ionization energy[61] Low to high Moderate to very high
Electronegativity[62] Low to high Moderate to very high

Nonmetals have relatively high values of electronegativity, and their oxides are usually acidic. Exceptions may occur if a nonmetal is not very electronegative, or if its oxidation state is low, or both. These non-acidic oxides of nonmetals may be amphoteric (like water, H2O[63]) or neutral (like nitrous oxide, N2O[64][h]), but never basic.

Nonmetals tend to gain electrons during chemical reactions, in contrast to metals which tend to donate electrons. This behavior is related to the stability of electron configurations in the noble gases, which have complete outer shells as summarized by the duet and octet rules of thumb, more correctly explained in terms of valence bond theory.[67]

They typically exhibit higher ionization energies, electron affinities, and standard electrode potentials than metals. Generally, the higher these values are (including electronegativity) the more nonmetallic the element tends to be.[68] For example, the chemically very active nonmetals fluorine, chlorine, bromine, and iodine have an average electronegativity of 3.19—a figure[i] higher than that of any metallic element.

The chemical distinctions between metals and nonmetals is connected to the attractive force between the positive nuclear charge of an individual atom and its negatively charged outer electrons. From left to right across each period of the periodic table, the nuclear charge (number of protons in the atomic nucleus) increases.[69] There is a corresponding reduction in atomic radius[70] as the increased nuclear charge draws the outer electrons closer to the nuclear core.[71] In chemical bonding, nonmetals tend to gain electrons due to their higher nuclear charge, resulting in negatively charged ions.[72]

The number of compounds formed by nonmetals is vast.[73] The first 10 places in a "top 20" table of elements most frequently encountered in 895,501,834 compounds, as listed in the Chemical Abstracts Service register for November 2, 2021, were occupied by nonmetals. Hydrogen, carbon, oxygen, and nitrogen collectively appeared in most (80%) of compounds. Silicon, a metalloid, ranked 11th. The highest-rated metal, with an occurrence frequency of 0.14%, was iron, in 12th place.[74] A few examples of nonmetal compounds are: boric acid (H
3BO
3), used in ceramic glazes;[75] selenocysteine (C
3H
7NO
2Se), the 21st amino acid of life;[76] phosphorus sesquisulfide (P4S3), found in strike anywhere matches;[77] and teflon ((C
2F
4)n), used to create non-stick coatings for pans and other cookware.[78]

Complications

[edit]

Adding complexity to the chemistry of the nonmetals are anomalies occurring in the first row of each periodic table block; non-uniform periodic trends; higher oxidation states; multiple bond formation; and property overlaps with metals.

First row anomaly

[edit]
A table with seven rows and ten columns. Rows are labeled on the left with a period number from 1 through 7. Columns are labeled on the bottom with a group number. Most cells represent a single chemical element and have two lines of information: the element's symbol on the top and its atomic number on the bottom. The table as a whole is divided into four rectangular areas separated from each other by narrow gaps. The first rectangle fills all seven rows of the first two columns. The rectangle is labeled "s-block" at the top and its two columns are labeled with group numbers "(1)" and "(2)" on the bottom. The cells in the first row - hydrogen and helium, with symbols H and He and atomic numbers 1 and 2 respectively - are both shaded red. The second rectangle fills the bottom two rows (periods 6 and 7) of the third column. Just above these cells is the label "f-block"; there is no group label on the bottom. The topmost cell - labeled "La-Yb" for elements 57-70 - is shaded green. The third rectangle fills the bottom four rows (periods 4 through 7) of the fourth column. Just above these cells is the label "d-block"; at the bottom is the label "(3-12)" for the group numbers of these elements. The topmost cell - labeled "Sc-Zn" for elements 21-30 - is shaded blue. The fourth and last rectangle fills the bottom six rows (periods 2 through 7) of the last six columns. Just above these cells is the label "p-block"; at the bottom are labels "(13)" through "(18) for the group numbers of these elements. The cells in the topmost row - for the elements boron (B,5), carbon (C,6), nitrogen (N,7), oxygen (O,8), fluorine (Fl,9), and neon (Ne,10) - are shaded yellow. Bold lines encircle the cells of the nonmetals - the top two cells on the left and 21 cells in the upper right of the table.
Condensed periodic table highlighting
the first row of each block:  s   p   d  and  f 
Period s-block
1 H
1 		He
2
p-block
2 Li
3 		Be
4 		B
5 		C
6 		N
7 		O
8 		F
9 		Ne
10
3 Na
11 		Mg
12
d-block 		Al
13 		Si
14 		P
15 		S
16 		Cl
17 		Ar
18
4 K
19 		Ca
20 		Sc-Zn
21-30 		Ga
31 		Ge
32 		As
33 		Se
34 		Br
35 		Kr
36
5 Rb
37 		Sr
38
f-block 		Y-Cd
39-48 		In
49 		Sn
50 		Sb
51 		Te
52 		I
53 		Xe
54
6 Cs
55 		Ba
56 		La-Yb
57-70 		Lu-Hg
71-80 		Tl
81 		Pb
82 		Bi
83 		Po
84 		At
85 		Rn
86
7 Fr
87 		Ra
88 		Ac-No
89-102 		Lr-Cn
103-112 		Nh
113 		Fl
114 		Mc
115 		Lv
116 		Ts
117 		Og
118
Group (1) (2) (3-12) (13) (14) (15) (16) (17) (18)
The first-row anomaly strength by block is s >> p > d > f.[79][j]

Starting with hydrogen, the first row anomaly primarily arises from the electron configurations of the elements concerned. Hydrogen is notable for its diverse bonding behaviors. It most commonly forms covalent bonds, but it can also lose its single electron in an aqueous solution, leaving behind a bare proton with tremendous polarizing power.[80] Consequently, this proton can attach itself to the lone electron pair of an oxygen atom in a water molecule, laying the foundation for acid-base chemistry.[81] Moreover, a hydrogen atom in a molecule can form a second, albeit weaker, bond with an atom or group of atoms in another molecule. Such bonding, "helps give snowflakes their hexagonal symmetry, binds DNA into a double helix; shapes the three-dimensional forms of proteins; and even raises water's boiling point high enough to make a decent cup of tea."[82]

Hydrogen and helium, as well as boron through neon, have unusually small atomic radii. This phenomenon arises because the 1s and 2p subshells lack inner analogues (meaning there is no zero shell and no 1p subshell), and they therefore experience less electron-electron exchange interactions, unlike the 3p, 4p, and 5p subshells of heavier elements.[83][dubious – discuss] As a result, ionization energies and electronegativities among these elements are higher than the periodic trends would otherwise suggest. The compact atomic radii of carbon, nitrogen, and oxygen facilitate the formation of double or triple bonds.[84]

While it would normally be expected, on electron configuration consistency grounds, that hydrogen and helium would be placed atop the s-block elements, the significant first row anomaly shown by these two elements justifies alternative placements. Hydrogen is occasionally positioned above fluorine, in group 17, rather than above lithium in group 1. Helium is almost always placed above neon, in group 18, rather than above beryllium in group 2.[85]

Secondary periodicity

[edit]
A graph with a vertical electronegativity axis and a horizontal atomic number axis. The five elements plotted are O, S, Se, Te and Po. The electronegativity of Se looks too high, and causes a bump in what otherwise be a smooth curve.
Electronegativity values of the group 16 chalcogen elements showing a W-shaped alternation or secondary periodicity going down the group

An alternation in certain periodic trends, sometimes referred to as secondary periodicity, becomes evident when descending groups 13 to 15, and to a lesser extent, groups 16 and 17.[86][k] Immediately after the first row of d-block metals, from scandium to zinc, the 3d electrons in the p-block elements—specifically, gallium (a metal), germanium, arsenic, selenium, and bromine—prove less effective at shielding the increasing positive nuclear charge.

The Soviet chemist Shchukarev [ru] gives two more tangible examples:[88]

"The toxicity of some arsenic compounds, and the absence of this property in analogous compounds of phosphorus [P] and antimony [Sb]; and the ability of selenic acid [H2SeO4] to bring metallic gold [Au] into solution, and the absence of this property in sulfuric [H2SO4] and [H2TeO4] acids."

Higher oxidation states

[edit]
Roman numerals such as III, V and VIII denote oxidation states

Some nonmetallic elements exhibit oxidation states that deviate from those predicted by the octet rule, which typically results in an oxidation state of –3 in group 15, –2 in group 16, –1 in group 17, and 0 in group 18. Examples include ammonia NH3, hydrogen sulfide H2S, hydrogen fluoride HF, and elemental xenon Xe. Meanwhile, the maximum possible oxidation state increases from +5 in group 15, to +8 in group 18. The +5 oxidation state is observable from period 2 onward, in compounds such as nitric acid HN(V)O3 and phosphorus pentafluoride PCl5.[l] Higher oxidation states in later groups emerge from period 3 onwards, as seen in sulfur hexafluoride SF6, iodine heptafluoride IF7, and xenon(VIII) tetroxide XeO4. For heavier nonmetals, their larger atomic radii and lower electronegativity values enable the formation of compounds with higher oxidation numbers, supporting higher bulk coordination numbers.[89]

Multiple bond formation

[edit]
A chain of five N's in a wing shape
Molecular structure of pentazenium, a homopolyatomic cation of nitrogen with the formula N5+ and structure N−N−N−N−N.[90]

Period 2 nonmetals, particularly carbon, nitrogen, and oxygen, show a propensity to form multiple bonds. The compounds formed by these elements often exhibit unique stoichiometries and structures, as seen in the various nitrogen oxides,[89] which are not commonly found in elements from later periods.

Property overlaps

[edit]

While certain elements have traditionally been classified as nonmetals and others as metals, some overlapping of properties occurs. Writing early in the twentieth century, by which time the era of modern chemistry had been well-established,[91] Humphrey[92] observed that:

... these two groups, however, are not marked off perfectly sharply from each other; some nonmetals resemble metals in certain of their properties, and some metals approximate in some ways to the non-metals.
An open glass jar with a brown powder in it
Boron (here in its less stable amorphous form) shares some similarities with metals[m]

Examples of metal-like properties occurring in nonmetallic elements include:

  • Silicon has an electronegativity (1.9) comparable with metals such as cobalt (1.88), copper (1.9), nickel (1.91) and silver (1.93);[62]
  • The electrical conductivity of graphite exceeds that of some metals;[n]
  • Selenium can be drawn into a wire;[51]
  • Radon is the most metallic of the noble gases and begins to show some cationic behavior, which is unusual for a nonmetal;[96] and
  • In extreme conditions, just over half of nonmetallic elements can form homopolyatomic cations.[o]

Examples of nonmetal-like properties occurring in metals are:

  • Tungsten displays some nonmetallic properties, sometimes being brittle, having a high electronegativity, and forming only anions in aqueous solution,[98] and predominately acidic oxides.[9][99]
  • Gold, the "king of metals" has the highest electrode potential among metals, suggesting a preference for gaining rather than losing electrons. Gold's ionization energy is one of the highest among metals, and its electron affinity and electronegativity are high, with the latter exceeding that of some nonmetals. It forms the Au– auride anion and exhibits a tendency to bond to itself, behaviors which are unexpected for metals. In aurides (MAu, where M = Li–Cs), gold's behavior is similar to that of a halogen.[100] Gold has a large enough nuclear potential that the electrons have to be considered with relativistic effects included which changes some of the properties.[101]

A relatively recent development involves certain compounds of heavier p-block elements, such as silicon, phosphorus, germanium, arsenic and antimony, exhibiting behaviors typically associated with transition metal complexes. This is linked to a small energy gap between their filled and empty molecular orbitals, which are the regions in a molecule where electrons reside and where they can be available for chemical reactions. In such compounds, this allows for unusual reactivity with small molecules like hydrogen (H2), ammonia (NH3), and ethylene (C2H4), a characteristic previously observed primarily in transition metal compounds. These reactions may open new avenues in catalytic applications.[102]

Types

[edit]

Nonmetal classification schemes vary widely, with some accommodating as few as two subtypes and others identifying up to seven. For example, the periodic table in the Encyclopaedia Britannica recognizes noble gases, halogens, and other nonmetals, and splits the elements commonly recognized as metalloids between "other metals" and "other nonmetals".[103] On the other hand, seven of twelve color categories on the Royal Society of Chemistry periodic table include nonmetals.[104][p]

Group (1, 13−18) Period
13 14 15 16 1/17 18 (1−6)
  H He 1
  B C N O F Ne 2
  Si P S Cl Ar 3
  Ge As Se Br Kr 4
  Sb Te I Xe 5
  Rn 6

Starting on the right side of the periodic table, three types of nonmetals can be recognized:

   the relatively inert noble gases—helium, neon, argon, krypton, xenon, radon;[105]
   the notably reactive halogen nonmetals—fluorine, chlorine, bromine, iodine;[106] and
   the mixed reactivity "unclassified nonmetals", a set with no widely used collective name—hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, selenium.[r] The descriptive phrase unclassified nonmetals is used here for convenience.

The elements in a fourth set are sometimes recognized as nonmetals:

   the generally unreactive[t] metalloids,[124] sometimes considered a third category distinct from metals and nonmetals—boron, silicon, germanium, arsenic, antimony, tellurium.

While many of the early workers attempted to classify elements none of their classifications were satisfactory. They were divided into metals and nonmetals, but some were soon found to have properties of both. These were called metalloids. This only added to the confusion by making two indistinct divisions where one existed before.[125]

Whiteford & Coffin 1939, Essentials of College Chemistry

The boundaries between these types are not sharp.[u] Carbon, phosphorus, selenium, and iodine border the metalloids and show some metallic character, as does hydrogen.

The greatest discrepancy between authors occurs in metalloid "frontier territory".[127] Some consider metalloids distinct from both metals and nonmetals, while others classify them as nonmetals.[4] Some categorize certain metalloids as metals (e.g., arsenic and antimony due to their similarities to heavy metals).[128][v] Metalloids resemble the elements universally considered "nonmetals" in having relatively low densities, high electronegativity, and similar chemical behavior.[124][w]

Noble gases

[edit]
Main article: Noble gas
a glass tube, held upside down by some tongs, has a clear-looking ice-like plug in it which is slowly melting judging from the clear drops falling out of the open end of the tube
A small (about 2 cm long) piece of rapidly melting argon ice

Six nonmetals are classified as noble gases: helium, neon, argon, krypton, xenon, and the radioactive radon. In conventional periodic tables they occupy the rightmost column. They are called noble gases due to their exceptionally low chemical reactivity.[105]

These elements exhibit similar properties, characterized by their colorlessness, odorlessness, and nonflammability. Due to their closed outer electron shells, noble gases possess weak interatomic forces of attraction, leading to exceptionally low melting and boiling points.[129] As a consequence, they all exist as gases under standard conditions, even those with atomic masses surpassing many typically solid elements.[130]

Chemically, the noble gases exhibit relatively high ionization energies, negligible or negative electron affinities, and high to very high electronegativities. The number of compounds formed by noble gases is in the hundreds and continues to expand,[131] with most of these compounds involving the combination of oxygen or fluorine with either krypton, xenon, or radon.[132]

Halogen nonmetals

[edit]
Main article: Halogen
Silver chunks covered be a clear liquid in a sealed bottle
A small pile of white crystals in front of a tipped-over cylindrical with a few grains spilling out of the holes in its screw-top lid
A translucent pale yellow gas in a sealed bottle
Highly reactive sodium metal (Na, left) combines with corrosive halogen nonmetal chlorine gas (Cl, right) to form stable, unreactive table salt (NaCl, center).

While the halogen nonmetals are notably reactive and corrosive elements, they can also be found in everyday compounds like toothpaste (NaF); common table salt (NaCl); swimming pool disinfectant (NaBr); and food supplements (KI). The term "halogen" itself means "salt former".[133]

Chemically, the halogen nonmetals exhibit high ionization energies, electron affinities, and electronegativity values, and are mostly relatively strong oxidizing agents.[134] These characteristics contribute to their corrosive nature.[135] All four elements tend to form primarily ionic compounds with metals,[136] in contrast to the remaining nonmetals (except for oxygen) which tend to form primarily covalent compounds with metals.[x] The highly reactive and strongly electronegative nature of the halogen nonmetals epitomizes nonmetallic character.[140]

Unclassified nonmetals

[edit]

A small glass jar filled with small dull grey concave buttons. The pieces of selenium look like tiny mushrooms without their stems.
Selenium conducts electricity around 1,000 times better when light falls on it, a property used in light-sensing applications.[141]

Hydrogen behaves in some respects like a metallic element and in others like a nonmetal.[142] Like a metallic element it can, for example, form a solvated cation in aqueous solution;[143] it can substitute for alkali metals in compounds such as the chlorides (NaCl cf. HCl) and nitrates (KNO3 cf. HNO3), and in certain alkali metal complexes[144][145] as a nonmetal.[146] It attains this configuration by forming a covalent or ionic bond[147] or, if it has initially given up its electron, by attaching itself to a lone pair of electrons.[148]

Some or all of these nonmetals share several properties. Being generally less reactive than the halogens,[149] most of them can occur naturally in the environment.[150] They have significant roles in biology[151] and geochemistry.[152] Collectively, their physical and chemical characteristics can be described as "moderately non-metallic".[152] Sometimes they have corrosive aspects. Carbon corrosion can occur in fuel cells.[153] Untreated selenium in soils can lead to the formation of corrosive hydrogen selenide gas.[154] Very different, when combined with metals, the unclassified nonmetals can form interstitial or refractory compounds[155] due to their relatively small atomic radii and sufficiently low ionization energies.[152] They also exhibit a tendency to bond to themselves, particularly in solid compounds.[156] Additionally, diagonal periodic table relationships among these nonmetals mirror similar relationships among the metalloids.[157]

Abundance, extraction, and uses

[edit]

Abundance

[edit]
Approximate composition
(top three components by weight)
Universe[158] 75% hydrogen 23% helium 1% oxygen
Atmosphere[159] 78% nitrogen 21% oxygen 0.5% argon
Hydrosphere[160] 86% oxygen 11% hydrogen 2% chlorine
Biomass[161] 63% oxygen 20% carbon 10% hydrogen
Crust[160] 46% oxygen 27% silicon 8% aluminium

The abundance of elements in the universe results from nuclear physics processes like nucleosynthesis and radioactive decay.

The volatile noble gas nonmetal elements are less abundant in the atmosphere than expected based their overall abundance due to cosmic nucleosynthesis. Mechanisms to explain this difference is an important aspect of planetary science.[162] Even within that challenge, the nonmetal element Xe is unexpectedly depleted. A possible explanation comes from theoretical models of the high pressures in the Earth's core suggest there may be around 1013 tons of xenon, in the form of stable XeFe3 and XeNi3 intermetallic compounds.[163]

Five nonmetals—hydrogen, carbon, nitrogen, oxygen, and silicon—form the bulk of the directly observable structure of the Earth: about 73% of the crust, 93% of the biomass, 96% of the hydrosphere, and over 99% of the atmosphere, as shown in the accompanying table. Silicon and oxygen form highly stable tetrahedral structures, known as silicates. Here, "the powerful bond that unites the oxygen and silicon ions is the cement that holds the Earth's crust together."[164]

In the biomass, the relative abundance of the first four nonmetals (and phosphorus, sulfur, and selenium marginally) is attributed to a combination of relatively small atomic size, and sufficient spare electrons. These two properties enable them to bind to one another and "some other elements, to produce a molecular soup sufficient to build a self-replicating system."[165]

Extraction

[edit]

Nine of the 23 nonmetallic elements are gases, or form compounds that are gases, and are extracted from natural gas or liquid air. These elements include hydrogen, helium, nitrogen, oxygen, neon, sulfur, argon, krypton, and xenon. For example, nitrogen and oxygen are extracted from air through fractional distillation of liquid air. This method capitalizes on their different boiling points to separate them efficiently.[166] Sulfur was extracted using the Frasch process, which involved injecting superheated water into underground deposits to melt the sulfur, which is then pumped to the surface. This technique leveraged sulfur's low melting point relative to other geological materials. It is now obtained by reacting the hydrogen sulfide in natural gas, with oxygen. Water is formed, leaving the sulfur behind.[167]

Nonmetallic elements are extracted from the following sources:[150]

Group (1, 13−18) Period
13 14 15 16 1/17 18 (1−6)
  H He 1
  B C N O F Ne 2
  Si P S Cl Ar 3
  Ge As Se Br Kr 4
  Sb Te I Xe 5
  Rn 6
   Gases (3): hydrogen, from methane; helium, from natural gas; sulfur, from hydrogen sulfide in natural gas
   Liquids (9): nitrogen, oxygen, neon, argon, krypton and xenon from liquid air; chlorine, bromine and iodine from brine
   Solids (12): boron, from borates; carbon occurs naturally as graphite; silicon, from silica; phosphorus, from phosphates; iodine, from sodium iodate; radon, as a decay product from uranium ores; fluorine, from fluorite;[y] germanium, arsenic, selenium, antimony and tellurium, from sulfides.

Uses

[edit]

Uses of nonmetals and non-metallic elements are broadly categorized as domestic, industrial, attenuative (lubricative, retarding, insulating or cooling), and agricultural

Many have domestic and industrial applications in household accoutrements;[169][z] medicine and pharmaceuticals;[171] and lasers and lighting.[172] They are components of mineral acids;[173] and prevalent in plug-in hybrid vehicles;[174] and smartphones.[175]

A significant number have attenuative and agricultural applications. They are used in lubricants;[176] and flame retardants and fire extinguishers.[177] They can serve as inert air replacements;[178] and are used in cryogenics and refrigerants.[179] Their significance extends to agriculture, through their use in fertilizers.[180]

Additionally, a smaller number of nonmetals or nonmetallic elements find specialized uses in explosives;[181] and welding gases.[182]

Taxonomical history

[edit]

Background

[edit]
A stone sculpture of the head of a bearded man
Greek philosopher Aristotle (384–322 BCE) categorized substances found in the earth as either metals or "fossiles".

Around 340 BCE, in Book III of his treatise Meteorology, the ancient Greek philosopher Aristotle categorized substances found within the Earth into metals and "fossiles".[aa] The latter category included various minerals such as realgar, ochre, ruddle, sulfur, cinnabar, and other substances that he referred to as "stones which cannot be melted".[185]

Until the Middle Ages the classification of minerals remained largely unchanged, albeit with varying terminology. In the fourteenth century, the English alchemist Richardus Anglicus expanded upon the classification of minerals in his work Correctorium Alchemiae. In this text, he proposed the existence of two primary types of minerals. The first category, which he referred to as "major minerals", included well-known metals such as gold, silver, copper, tin, lead, and iron. The second category, labeled "minor minerals", encompassed substances like salts, atramenta (iron sulfate), alums, vitriol, arsenic, orpiment, sulfur, and similar substances that were not metallic bodies.[186]

The term "nonmetallic" dates back to at least the 16th century. In his 1566 medical treatise, French physician Loys de L'Aunay distinguished substances from plant sources based on whether they originated from metallic or non-metallic soils.[187]

Later, the French chemist Nicolas Lémery discussed metallic and nonmetallic minerals in his work Universal Treatise on Simple Drugs, Arranged Alphabetically published in 1699. In his writings, he contemplated whether the substance "cadmia" belonged to either the first category, akin to cobaltum (cobaltite), or the second category, exemplified by what was then known as calamine—a mixed ore containing zinc carbonate and silicate.[188]

A distinguished gentleman, seated and looking towards the view; a copy of his book "Traité élémentaire de chimie" is at his hand upon what looks to be a reading plinth
French nobleman and chemist Antoine Lavoisier (1743–1794), with a page of the English translation of his 1789 Traité élémentaire de chimie,[189] listing the elemental gases oxygen, hydrogen and nitrogen (and erroneously including light and caloric); the nonmetallic substances sulfur, phosphorus, and carbon; and the chloride, fluoride and borate ions

Organization of elements by types

[edit]
See also: Discovery of chemical elements

Just as the ancients distinguished metals from other minerals, similar distinctions developed as the modern idea of chemical elements emerged in the late 1700s. French chemist Antoine Lavoisier published the first modern list of chemical elements in his revolutionary[190] 1789 Traité élémentaire de chimie. The 33 elements known to Lavoisier were categorized into four distinct groups, including gases, metallic substances, nonmetallic substances that form acids when oxidized,[191] and earths (heat-resistant oxides).[192] Lavoisier's work gained widespread recognition and was republished in twenty-three editions across six languages within its first seventeen years, significantly advancing the understanding of chemistry in Europe and America.[193]

In 1802 the term "metalloids" was introduced for elements with the physical properties of metals but the chemical properties of non-metals.[194] However, in 1811, the Swedish chemist Berzelius used the term "metalloids"[195] to describe all nonmetallic elements, noting their ability to form negatively charged ions with oxygen in aqueous solutions.[196][197] Thus in 1864, the "Manual of Metalloids" divided all elements into either metals or metalloids, with the latter group including elements now called nonmetals.[198]: 31  Reviews of the book indicated that the term "metalloids" was still endorsed by leading authorities,[199] but there were reservations about its appropriateness. While Berzelius' terminology gained significant acceptance,[200] it later faced criticism from some who found it counterintuitive,[197] misapplied,[201] or even invalid.[202][203] The idea of designating elements like arsenic as metalloids had been considered.[199] By as early as 1866, some authors began preferring the term "nonmetal" over "metalloid" to describe nonmetallic elements.[204] In 1875, Kemshead[205] observed that elements were categorized into two groups: non-metals (or metalloids) and metals. He noted that the term "non-metal", despite its compound nature, was more precise and had become universally accepted as the nomenclature of choice.

Development of types

[edit]
A side profile set in stone of a distinguished French gentleman
Bust of Dupasquier (1793–1848) in the Monument aux Grands Hommes de la Martinière [fr] in Lyon, France.

In 1844, Alphonse Dupasquier [fr], a French doctor, pharmacist, and chemist,[206] established a basic taxonomy of nonmetals to aid in their study. He wrote:[207]

They will be divided into four groups or sections, as in the following:
Organogens—oxygen, nitrogen, hydrogen, carbon
Sulphuroids—sulfur, selenium, phosphorus
Chloroides—fluorine, chlorine, bromine, iodine
Boroids—boron, silicon.

Dupasquier's quartet parallels the modern nonmetal types. The organogens and sulphuroids are akin to the unclassified nonmetals. The chloroides were later called halogens.[208] The boroids eventually evolved into the metalloids, with this classification beginning from as early as 1864.[199] The then unknown noble gases were recognized as a distinct nonmetal group after being discovered in the late 1800s.[209]

His taxonomy was noted for its natural basis.[210][ab] That said, it was a significant departure from other contemporary classifications, since it grouped together oxygen, nitrogen, hydrogen, and carbon.[212]

In 1828 and 1859, the French chemist Dumas classified nonmetals as (1) hydrogen; (2) fluorine to iodine; (3) oxygen to sulfur; (4) nitrogen to arsenic; and (5) carbon, boron and silicon,[213] thereby anticipating the vertical groupings of Mendeleev's 1871 periodic table. Dumas' five classes fall into modern groups 1, 17, 16, 15, and 14 to 13 respectively.

Suggested distinguishing criteria

[edit]
Properties suggested
to distinguish metals from nonmetals
Year Property and type
1803 General properties[214]  P
1906 Hydrolysis of halides[215] C
1911 Cation formation[216][dubious – discuss] C
1927 Goldhammer-Herzfeld
metallization criterion[ac][218]		 P
1931 Electron band structure[219] A
1949 Bulk coordination number[220] P
1956 Temperature coefficient
of resistivity[221]		 C
1956 Acid-base nature of oxides[222] C
1962 Sonorousness[ad][223] P
1969 Melting and boiling points,
electrical conductivity[224]		 P
1977 Sulfate formation[59] C
1977 Oxide solubility in acids[225] C
1986 Enthalpy of vaporization[226] P
1991 Liquid range[ae][227] P
1998 Electrical conductivity
at absolute zero[219]		 P
1999 Element structure (in bulk)[228][dubious – discuss] P
2001 Packing efficiency[229] P
2020 Mott parameter[af][230] A
Physical/Chemical/Atomic: P/C/A

Much of the early analyses were phenomenological, and a variety of physical, chemical, and atomic properties have been suggested for distinguishing metals from nonmetals (or other bodies); a comprehensive early set of characteristics was stated by Rev Thaddeus Mason Harrisn in the 1803 Minor Encyclopedia .[214]

METAL, in natural history and chemistry, the name of a class of simple bodies; of which it is observed, that they posses; a lustre; that they are opaque; that they arc fusible, or may be melted; that their specific gravity is greater than that of any other bodies yet discovered; that they are better conductors of electricity, than any other body; that they are malleable, or capable of being extended and flattened by the hammer; and that they are ductile or tenacious, that is, capable of being drawn out into threads or wires.

Some criteria did not last long; for instance in 1809, the British chemist and inventor Humphry Davy isolated sodium and potassium,[231] their low densities contrasted with their metallic appearance, so the density property was tenuous although these metals was firmly established by their chemical properties.[232]

Johnson[233] has a similar approach to Mason, distinguishing between metals and nonmetals on the basis of their physical states, electrical conductivity, mechanical properties, and the acid-base nature of their oxides:

  1. gaseous elements are nonmetals (hydrogen, nitrogen, oxygen, fluorine, chlorine and the noble gases);
  2. liquids (mercury, bromine) are either metallic or nonmetallic: mercury, as a good conductor, is a metal; bromine, with its poor conductivity, is a nonmetal;
  3. solids are either ductile and malleable, hard and brittle, or soft and crumbly:
a. ductile and malleable elements are metals;
b. hard and brittle elements include boron, silicon and germanium, which are semiconductors and therefore not metals; and
c. soft and crumbly elements include carbon, phosphorus, sulfur, arsenic, antimony,[ag] tellurium and iodine, which have acidic oxides indicative of nonmetallic character.[ah]
Density and electronegativity in the periodic table[ai]
H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
Cs Ba 1 asterisk Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po Rn
Ra 1 asterisk
                                                                                                                                               
1 asterisk La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
1 asterisk Ac Th Pa U Np Pu Am Cm Bk Cf Es
Electronegativity (EN): < 1.9 ≥ 1.9 (revised Pauling)
Density (D):  < 7 g/cm3 
           
           
D < 7 and EN ≥ 1.9 for all nonmetallic elements
≥ 7 g/cm3 
           
           
D ≥ 7 or EN < 1.9 (or both) for all metals

Several authors[238] have noted that nonmetals generally have low densities and high electronegativity. The accompanying table, using a threshold of 7 g/cm3 for density and 1.9 for electronegativity (revised Pauling), shows that all nonmetals have low density and high electronegativity. In contrast, all metals have either high density or low electronegativity (or both). Goldwhite and Spielman[239] added that, "... lighter elements tend to be more electronegative than heavier ones." The average electronegativity for the elements in the table with densities less than 7 gm/cm3 (metals and nonmetals) is 1.97 compared to 1.66 for the metals having densities of more than 7 gm/cm3.

There is not full agreement about the use of phenomenological properties. Emsley[240] pointed out the complexity of this task, asserting that no single property alone can unequivocally assign elements to either the metal or nonmetal category. Some authors divide elements into metals, metalloids, and nonmetals, but Oderberg[241] disagrees, arguing that by the principles of categorization, anything not classified as a metal should be considered a nonmetal.

Kneen and colleagues[242] proposed that the classification of nonmetals can be achieved by establishing a single criterion for metallicity. They acknowledged that various plausible classifications exist and emphasized that while these classifications may differ to some extent, they would generally agree on the categorization of nonmetals. The describe electrical conductivity as the key property, arguing that this is the most common approach.

One of the most commonly recognized properties used is the temperature coefficient of resistivity, the effect of heating on electrical resistance and conductivity. As temperature rises, the conductivity of metals decreases while that of nonmetals increases.[243] However, plutonium, carbon, arsenic, and antimony appear to defy the norm. When plutonium (a metal) is heated within a temperature range of −175 to +125 °C its conductivity increases.[244] Similarly, despite its common classification as a nonmetallic element, carbon (as graphite) is a semimetal which when heated experiences a decrease in electrical conductivity.[245] Arsenic and antimony, which are occasionally classified as nonmetallic elements are also semimetals, and show behavior similar to carbon.[246][dubious – discuss]

Comparison of selected properties

[edit]

The two tables in this section list some of the properties of five types of elements (noble gases, halogen nonmetals, unclassified nonmetals, metalloids and, for comparison, metals) based on their most stable forms at standard temperature and pressure. The dashed lines around the columns for metalloids signify that the treatment of these elements as a distinct type can vary depending on the author, or classification scheme in use.

Physical properties by element type

[edit]
See also § Physical

Physical properties are listed in loose order of ease of their determination.

Property Element type
Metals Metalloids Unc. nonmetals Halogen nonmetals Noble gases
General physical appearance lustrous[20] lustrous[247]
  • ◇ lustrous: carbon, phosphorus, selenium[248]
  • ◇ colored: sulfur[249]
  • ◇ colorless: hydrogen, nitrogen, oxygen[250]
  • ◇ lustrous: iodine[3]
  • ◇ colored: fluorine, chlorine, bromine[251]
 colorless[252]
Form and density[253] solid
(Hg liquid) 		solid solid or gas solid or gas
(bromine liquid) 		gas
often high density such as iron, lead, tungsten low to moderately high density low density low density low density
some light metals including beryllium, magnesium, aluminium all lighter than iron hydrogen, nitrogen lighter than air[254] helium, neon lighter than air[255]
Plasticity mostly malleable and ductile[20] often brittle[247] phosphorus, sulfur, selenium, brittle[aj] iodine brittle[259] not applicable
Electrical conductivity good[ak]
  • ◇ moderate: boron, silicon, germanium, tellurium
  • ◇ good: arsenic, antimony[al]
  • ◇ poor: hydrogen, nitrogen, oxygen, sulfur
  • ◇ moderate: phosphorus, selenium
  • ◇ good: carbon[am]
  • ◇ poor: fluorine, chlorine, bromine
  • ◇ moderate: I[an]
 poor[ao]
Electronic structure[42] metal (beryllium, strontium, α-tin, ytterbium, bismuth are semimetals) semimetal (arsenic, antimony) or semiconductor
  • ◇ semimetal: carbon
  • ◇ semiconductor: phosphorus
  • ◇ insulator: hydrogen, nitrogen, oxygen, sulfur
 semiconductor (I) or insulator insulator

Chemical properties by element type

[edit]
See also § Chemical

Chemical properties are listed from general characteristics to more specific details.

Property Element type
Metals Metalloids Unc. nonmetals Halogen nonmetals Noble gases
General chemical behavior
weakly nonmetallic[ap] moderately nonmetallic[265] strongly nonmetallic[266]
  • ◇ inert to nonmetallic[267]
  • ◇ radon shows some cationic behavior[268]
Oxides basic; some amphoteric or acidic[9] amphoteric or weakly acidic[269][aq] acidic[ar] or neutral[as] acidic[at] metastable XeO3 is acidic;[276] stable XeO4 strongly so[277]
few glass formers[au] all glass formers[279] some glass formers[av] no glass formers reported no glass formers reported
ionic, polymeric, layer, chain, and molecular structures[281] polymeric in structure[282]
  • ◇ mostly molecular[282]
  • ◇ carbon, phosphorus, sulfur, selenium have 1+ polymeric forms
  • ◇ mostly molecular
  • ◇ iodine has a polymeric form, I2O5[283]
  • ◇ mostly molecular
  • ◇ XeO2 is polymeric[284]
Compounds with metals alloys[20] or intermetallic compounds[285] tend to form alloys or intermetallic compounds[286]
  • ◇ salt-like to covalent or metallic: hydrogen†, carbon, nitrogen, phosphorus, sulfur, selenium[11]
  • ◇ mainly ionic: oxygen[287]
 mainly ionic[136] simple compounds at STP not known[aw]
Ionization energy (kJ mol−1)[61] ‡ low to high moderate moderate to high high high to very high
376 to 1,007 762 to 947 941 to 1,402 1,008 to 1,681 1,037 to 2,372
average 643 average 833 average 1,152 average 1,270 average 1,589
Electronegativity (Pauling)[ax][62] ‡ low to high moderate moderate to high high high (radon) to very high
0.7 to 2.54 1.9 to 2.18 2.19 to 3.44 2.66 to 3.98 ca. 2.43 to 4.7
average 1.5 average 2.05 average 2.65 average 3.19 average 3.3

† Hydrogen can also form alloy-like hydrides[145]
‡ The labels low, moderate, high, and very high are arbitrarily based on the value spans listed in the table

See also

[edit]

Notes

[edit]
  1. ^ These six (boron, silicon, germanium, arsenic, antimony, and tellurium) are the elements commonly recognized as "metalloids",[3] a category sometimes counted as a subcategory of nonmetals and sometimes as a category separate from both metals and nonmetals.[4]
  2. ^ The most stable forms are: diatomic hydrogen H2; β-rhombohedral boron; graphite for carbon; diatomic nitrogen N2; diatomic oxygen O2; tetrahedral silicon; black phosphorus; orthorhombic sulfur S8; α-germanium; gray arsenic; gray selenium; gray antimony; gray tellurium; and diatomic iodine I2. All other nonmetallic elements have only one stable form at STP.[6]
  3. ^ At higher temperatures and pressures the numbers of nonmetals can be called into question. For example, when germanium melts it changes from a semiconducting metalloid to a metallic conductor with an electrical conductivity similar to that of liquid mercury.[13] At a high enough pressure, sodium (a metal) becomes a non-conducting insulator.[14]
  4. ^ The absorbed light may be converted to heat or re-emitted in all directions so that the emission spectrum is thousands of times weaker than the incident light radiation.[17]
  5. ^ Solid iodine has a silvery metallic appearance under white light at room temperature. At ordinary and higher temperatures it sublimes from the solid phase directly into a violet-colored vapor.[18]
  6. ^ The solid nonmetals have electrical conductivity values ranging from 10−18 S•cm−1 for sulfur[22] to 3 × 104 in graphite[23] or 3.9 × 104 for arsenic;[24] cf. 0.69 × 104 for manganese to 63 × 104 for silver, both metals.[22] The conductivity of graphite (a nonmetal) and arsenic (a metalloid nonmetal) exceeds that of manganese. Such overlaps show that it can be difficult to draw a clear line between metals and nonmetals.
  7. ^ Thermal conductivity values for metals range from 6.3 W m−1 K−1 for neptunium to 429 for silver; cf. antimony 24.3, arsenic 50, and carbon 2000.[22] Electrical conductivity values of metals range from 0.69 S•cm−1 × 104 for manganese to 63 × 104 for silver; cf. carbon 3 × 104,[23] arsenic 3.9 × 104 and antimony 2.3 × 104.[22]
  8. ^ While CO and NO are commonly referred to as being neutral, CO is a slightly acidic oxide, reacting with bases to produce formates (CO + OH− → HCOO−);[65] and in water, NO reacts with oxygen to form nitrous acid HNO2 (4NO + O2 + 2H2O → 4HNO2).[66]
  9. ^ Electronegativity values of fluorine to iodine are: 3.98 + 3.16 + 2.96 + 2.66 = 12.76/4 3.19.
  10. ^ Helium is shown above beryllium for electron configuration consistency purposes; as a noble gas it is usually placed above neon, in group 18.
  11. ^ The net result is an even-odd difference between periods (except in the s-block): elements in even periods have smaller atomic radii and prefer to lose fewer electrons, while elements in odd periods (except the first) differ in the opposite direction. Many properties in the p-block then show a zigzag rather than a smooth trend along the group. For example, phosphorus and antimony in odd periods of group 15 readily reach the +5 oxidation state, whereas nitrogen, arsenic, and bismuth in even periods prefer to stay at +3.[87]
  12. ^ Oxidation states, which denote hypothetical charges for conceptualizing electron distribution in chemical bonding, do not necessarily reflect the net charge of molecules or ions. This concept is illustrated by anions such as NO3−, where the nitrogen atom is considered to have an oxidation state of +5 due to the distribution of electrons. However, the net charge of the ion remains −1. Such observations underscore the role of oxidation states in describing electron loss or gain within bonding contexts, distinct from indicating the actual electrical charge, particularly in covalently bonded molecules.
  13. ^ Greenwood[93] commented that: "The extent to which metallic elements mimic boron (in having fewer electrons than orbitals available for bonding) has been a fruitful cohering concept in the development of metalloborane chemistry ... Indeed, metals have been referred to as "honorary boron atoms" or even as "flexiboron atoms". The converse of this relationship is clearly also valid."
  14. ^ For example, the conductivity of graphite is 3 × 104 S•cm−1.[94] whereas that of manganese is 6.9 × 103 S•cm−1.[95]
  15. ^ A homopolyatomic cation consists of two or more atoms of the same element bonded together and carrying a positive charge, for example, N5+, O2+ and Cl4+. This is unusual behavior for nonmetals since cation formation is normally associated with metals, and nonmetals are normally associated with anion formation. Homopolyatomic cations are further known for carbon, phosphorus, antimony, sulfur, selenium, tellurium, bromine, iodine and xenon.[97]
  16. ^ Of the twelve categories in the Royal Society periodic table, five only show up with the metal filter, three only with the nonmetal filter, and four with both filters. Interestingly, the six elements marked as metalloids (boron, silicon, germanium, arsenic, antimony, and tellurium) show under both filters. Six other elements (113–118: nihonium, flerovium, moscovium, livermorium, tennessine, and oganesson), whose status is unknown, also show up under both filters but are not included in any of the twelve color categories.
  17. ^ The quote marks are not found in the source; they are used here to make it clear that the source employs the word non-metals as a formal term for the subset of chemical elements in question, rather than applying to nonmetals generally.
  18. ^ Varying configurations of these nonmetals have been referred to as, for example, basic nonmetals,[107] bioelements,[108] central nonmetals,[109] CHNOPS,[110] essential elements,[111] "non-metals",[112][q] orphan nonmetals,[113] or redox nonmetals.[114]
  19. ^ Arsenic is stable in dry air. Extended exposure in moist air results in the formation of a black surface coating. "Arsenic is not readily attacked by water, alkaline solutions or non-oxidizing acids".[119] It can occasionally be found in nature in an uncombined form.[120] It has a positive standard reduction potential (As → As3+ + 3e = +0.30 V), corresponding to a classification of semi-noble metal.[121]
  20. ^ "Crystalline boron is relatively inert."[115] Silicon "is generally highly unreactive."[116] "Germanium is a relatively inert semimetal."[117] "Pure arsenic is also relatively inert."[118][s] "Metallic antimony is … inert at room temperature."[122] "Compared to S and Se, Te has relatively low chemical reactivity."[123]
  21. ^ Boundary fuzziness and overlaps often occur in classification schemes.[126]
  22. ^ Jones takes a philosophical or pragmatic view to these questions. He writes: "Though classification is an essential feature of all branches of science, there are always hard cases at the boundaries. The boundary of a class is rarely sharp ... Scientists should not lose sleep over the hard cases. As long as a classification system is beneficial to economy of description, to structuring knowledge and to our understanding, and hard cases constitute a small minority, then keep it. If the system becomes less than useful, then scrap it and replace it with a system based on different shared characteristics."[126]
  23. ^ For a related comparison of the properties of metals, metalloids, and nonmetals, see Rudakiya & Patel (2021), p. 36.
  24. ^ Metal oxides are usually somewhat ionic, depending upon the metal element electropositivity.[137] On the other hand, oxides of metals with high oxidation states are often either polymeric or covalent.[138] A polymeric oxide has a linked structure composed of multiple repeating units.[139]
  25. ^ Exceptionally, a study reported in 2012 noted the presence of 0.04% native fluorine (F
    2    ) by weight in antozonite, attributing these inclusions to radiation from tiny amounts of uranium.[168]
  26. ^ Radon sometimes occurs as potentially hazardous indoor pollutant[170]
  27. ^ The term "fossile" is not to be confused with the modern usage of fossil to refer to the preserved remains, impression, or trace of any once-living thing.
  28. ^ A natural classification was based on "all the characters of the substances to be classified as opposed to the 'artificial classifications' based on one single character" such as the affinity of metals for oxygen. "A natural classification in chemistry would consider the most numerous and most essential analogies."[211]
  29. ^ The Goldhammer-Herzfeld ratio is roughly equal to the cube of the atomic radius divided by the molar volume.[217] More specifically, it is the ratio of the force holding an individual atom's outer electrons in place with the forces on the same electrons from interactions between the atoms in the solid or liquid element. When the interatomic forces are greater than, or equal to, the atomic force, outer electron itinerancy is indicated and metallic behavior is predicted. Otherwise nonmetallic behavior is anticipated.
  30. ^ Sonorousness is making a ringing sound when struck.
  31. ^ Liquid range is the difference between melting point and boiling point.
  32. ^ The Mott parameter is N 1/3ɑ*H where N the number of atoms per unit volume, and ɑ*H "is their effective size, usually taken as the effective Bohr radius of the maximum in the outermost (valence) electron probability distribution." In ambient conditions, a value of 0.45 is given for the value for the dividing line between metals and nonmetals.
  33. ^ While antimony trioxide is usually listed as being amphoteric its very weak acid properties dominate over those of a very weak base.[234]
  34. ^ Johnson counted boron as a nonmetal and silicon, germanium, arsenic, antimony, tellurium, polonium and astatine as "semimetals" i.e. metalloids.
  35. ^ (a) The table includes elements up to einsteinium (99) except for astatine (85) and francium (87), with densities and most electronegativities from Aylward and Findlay;[235] Electronegativities of noble gases are from Rahm, Zeng and Hoffmann.[236]
    (b) A survey of definitions of the term "heavy metal" reported density criteria ranging from above 3.5 g/cm3 to above 7 g/cm3;[237]
    (c) Vernon specified a minimum electronegativity of 1.9 for the metalloids, on the revised Pauling scale;[3]
  36. ^ All four have less stable non-brittle forms: carbon as exfoliated (expanded) graphite,[256][257] and as carbon nanotube wire;[258] phosphorus as white phosphorus (soft as wax, pliable and can be cut with a knife, at room temperature);[49] sulfur as plastic sulfur;[50] and selenium as selenium wires.[51]
  37. ^ Metals have electrical conductivity values of from 6.9×103 S•cm−1 for manganese to 6.3×105 for silver.[260]
  38. ^ Metalloids have electrical conductivity values of from 1.5×10−6 S•cm−1 for boron to 3.9×104 for arsenic.[261]
  39. ^ Unclassified nonmetals have electrical conductivity values of from ca. 1×10−18 S•cm−1 for the elemental gases to 3×104 in graphite.[94]
  40. ^ Halogen nonmetals have electrical conductivity values of from ca. 1×10−18 S•cm−1 for F and Cl to 1.7×10−8 S•cm−1 for iodine.[94][262]
  41. ^ Elemental gases have electrical conductivity values of ca. 1×10−18 S•cm−1.[94]
  42. ^ Metalloids always give "compounds less acidic in character than the corresponding compounds of the [typical] nonmetals."[247]
  43. ^ Arsenic trioxide reacts with sulfur trioxide, forming arsenic "sulfate" As2(SO4)3.[270] This substance is covalent in nature rather than ionic;[271] it is also given as As2O3·3SO3.[272]
  44. ^ NO
    2    , N
    2    O
    5    , SO
    3    , SeO
    3     are strongly acidic.[273]
  45. ^ H2O, CO, NO, N2O are neutral oxides; CO and N2O are "formally the anhydrides of formic and hyponitrous acid, respectively viz. CO + H2O → H2CO2 (HCOOH, formic acid); N2O + H2O → H2N2O2 (hyponitrous acid)."[274]
  46. ^ ClO
    2    , Cl
    2    O
    7    , I
    2    O
    5     are strongly acidic.[275]
  47. ^ Metals that form glasses are: vanadium; molybdenum, tungsten; alumnium, indium, thallium; tin, lead; and bismuth.[278]
  48. ^ Unclassified nonmetals that form glasses are phosphorus, sulfur, selenium;[278] CO2 forms a glass at 40 GPa.[280]
  49. ^ Disodium helide (Na2He) is a compound of helium and sodium that is stable at high pressures above 113 GPa. Argon forms an alloy with nickel, at 140 GPa and close to 1,500 K, however at this pressure argon is no longer a noble gas.[288]
  50. ^ Values for the noble gases are from Rahm, Zeng and Hoffmann.[236]

References

[edit]

Citations

[edit]
  1. ^ a b c Larrañaga, Lewis & Lewis 2016, p. 988
  2. ^ a b Steudel 2020, p. 43: Steudel's monograph is an updated translation of the fifth German edition of 2013, incorporating the literature up to Spring 2019.
  3. ^ a b c d e Vernon 2013
  4. ^ a b Goodrich 1844, p. 264; The Chemical News 1897, p. 189; Hampel & Hawley 1976, pp. 174, 191; Lewis 1993, p. 835; Hérold 2006, pp. 149–50
  5. ^ At: Restrepo et al. 2006, p. 411; Thornton & Burdette 2010, p. 86; Hermann, Hoffmann & Ashcroft 2013, pp. 11604‒1‒11604‒5; Cn: Mewes et al. 2019; Fl: Florez et al. 2022; Og: Smits et al. 2020
  6. ^ Wismer 1997, p. 72: H, He, C, N, O, F, Ne, S, Cl, Ar, As, Se, Br, Kr, Sb, I, Xe; Powell 1974, pp. 174, 182: P, Te; Greenwood & Earnshaw 2002, p. 143: B; Field 1979, p. 403: Si, Ge; Addison 1964, p. 120: Rn
  7. ^ Pascoe 1982, p. 3[broken anchor]
  8. ^ Malone & Dolter 2010, pp. 110–111
  9. ^ a b c Porterfield 1993, p. 336
  10. ^ Godovikov & Nenasheva 2020, p. 4; Morely & Muir 1892, p. 241
  11. ^ a b Vernon 2020, p. 220; Rochow 1966, p. 4
  12. ^ IUPAC Periodic Table of the Elements
  13. ^ Berger 1997, pp. 71–72
  14. ^ Gatti, Tokatly & Rubio 2010
  15. ^ Wibaut 1951, p. 33: "Many substances ...are colourless and therefore show no selective absorption in the visible part of the spectrum."
  16. ^ Elliot 1929, p. 629
  17. ^ Fox 2010, p. 31
  18. ^ Tidy 1887, pp. 107–108; Koenig 1962, p. 108
  19. ^ Wiberg 2001, p. 416; Wiberg is here referring to iodine.
  20. ^ a b c d e f Kneen, Rogers & Simpson 1972, pp. 261–264
  21. ^ a b Johnson 1966, p. 4
  22. ^ a b c d e Aylward & Findlay 2008, pp. 6–12
  23. ^ a b Jenkins & Kawamura 1976, p. 88
  24. ^ Carapella 1968, p. 30
  25. ^ Zumdahl & DeCoste 2010, pp. 455, 456, 469, A40; Earl & Wilford 2021, p. 3-24
  26. ^ Corb, B.W.; Wei, W.D.; Averbach, B.L. (1982). "Atomic models of amorphous selenium". Journal of Non-Crystalline Solids. 53 (1–2): 29–42. Bibcode:1982JNCS...53...29C. doi:10.1016/0022-3093(82)90016-3.
  27. ^ Wiberg 2001, pp. 780
  28. ^ Wiberg 2001, pp. 824, 785
  29. ^ Earl & Wilford 2021, p. 3-24
  30. ^ Siekierski & Burgess 2002, p. 86
  31. ^ Charlier, Gonze & Michenaud 1994
  32. ^ Taniguchi et al. 1984, p. 867: "... black phosphorus ... [is] characterized by the wide valence bands with rather delocalized nature."; Carmalt & Norman 1998, p. 7: "Phosphorus ... should therefore be expected to have some metalloid properties."; Du et al. 2010: Interlayer interactions in black phosphorus, which are attributed to van der Waals-Keesom forces, are thought to contribute to the smaller band gap of the bulk material (calculated 0.19 eV; observed 0.3 eV) as opposed to the larger band gap of a single layer (calculated ~0.75 eV).
  33. ^ Wiberg 2001, pp. 742
  34. ^ Evans 1966, pp. 124–25
  35. ^ Wiberg 2001, pp. 758
  36. ^ Stuke 1974, p. 178; Donohue 1982, pp. 386–87; Cotton et al. 1999, p. 501
  37. ^ Steudel 2020, p. 601: "... Considerable orbital overlap can be expected. Apparently, intermolecular multicenter bonds exist in crystalline iodine that extend throughout the layer and lead to the delocalization of electrons akin to that in metals. This explains certain physical properties of iodine: the dark color, the luster and a weak electric conductivity, which is 3400 times stronger within the layers then perpendicular to them. Crystalline iodine is thus a two-dimensional semiconductor."; Segal 1989, p. 481: "Iodine exhibits some metallic properties ..."
  38. ^ Taylor 1960, p. 207; Brannt 1919, p. 34
  39. ^ a b Green 2012, p. 14
  40. ^ Spencer, Bodner & Rickard 2012, p. 178
  41. ^ Redmer, Hensel & Holst 2010, preface
  42. ^ a b Keeler & Wothers 2013, p. 293
  43. ^ DeKock & Gray 1989, pp. 423, 426—427
  44. ^ Boreskov 2003, p. 45
  45. ^ a b Ashcroft and Mermin
  46. ^ Yang 2004, p. 9
  47. ^ Wiberg 2001, pp. 416, 574, 681, 824, 895, 930; Siekierski & Burgess 2002, p. 129
  48. ^ Weertman, Johannes; Weertman, Julia R. (1992). Elementary dislocation theory. New York: Oxford University Press. ISBN 978-0-19-506900-6.
  49. ^ a b Faraday 1853, p. 42; Holderness & Berry 1979, p. 255
  50. ^ a b Partington 1944, p. 405
  51. ^ a b c Regnault 1853, p. 208
  52. ^ Scharf, T. W.; Prasad, S. V. (January 2013). "Solid lubricants: a review". Journal of Materials Science. 48 (2): 511–531. Bibcode:2013JMatS..48..511S. doi:10.1007/s10853-012-7038-2. ISSN 0022-2461.
  53. ^ Barton 2021, p. 200
  54. ^ Wiberg 2001, p. 796
  55. ^ Shang et al. 2021
  56. ^ Tang et al. 2021
  57. ^ Steudel 2020, passim; Carrasco et al. 2023; Shanabrook, Lannin & Hisatsune 1981, pp. 130–133
  58. ^ Weller et al. 2018, preface
  59. ^ a b Abbott 1966, p. 18
  60. ^ Ganguly 2012, p. 1-1
  61. ^ a b Aylward & Findlay 2008, p. 132
  62. ^ a b c Aylward & Findlay 2008, p. 126
  63. ^ Eagleson 1994, 1169
  64. ^ Moody 1991, p. 365
  65. ^ House 2013, p. 427
  66. ^ Lewis & Deen 1994, p. 568
  67. ^ Smith 1990, pp. 177–189
  68. ^ Yoder, Suydam & Snavely 1975, p. 58
  69. ^ Young et al. 2018, p. 753
  70. ^ Brown et al. 2014, p. 227
  71. ^ Siekierski & Burgess 2002, pp. 21, 133, 177
  72. ^ Moore 2016; Burford, Passmore & Sanders 1989, p. 54
  73. ^ Brady & Senese 2009, p. 69
  74. ^ Chemical Abstracts Service 2021
  75. ^ Emsley 2011, pp. 81
  76. ^ Cockell 2019, p. 210
  77. ^ Scott 2014, p. 3
  78. ^ Emsley 2011, p. 184
  79. ^ Jensen 1986, p. 506
  80. ^ Lee 1996, p. 240
  81. ^ Greenwood & Earnshaw 2002, p. 43
  82. ^ Cressey 2010
  83. ^ Siekierski & Burgess 2002, pp. 24–25
  84. ^ Siekierski & Burgess 2002, p. 23
  85. ^ Petruševski & Cvetković 2018; Grochala 2018
  86. ^ Kneen, Rogers & Simpson 1972, pp. 226, 360; Siekierski & Burgess 2002, pp. 52, 101, 111, 124, 194
  87. ^ Scerri 2020, pp. 407–420
  88. ^ Shchukarev 1977, p. 229
  89. ^ a b Cox 2004, p. 146
  90. ^ Vij et al. 2001
  91. ^ Dorsey 2023, pp. 12–13
  92. ^ Humphrey 1908
  93. ^ Greenwood 2001, p. 2057
  94. ^ a b c d Bogoroditskii & Pasynkov 1967, p. 77; Jenkins & Kawamura 1976, p. 88
  95. ^ Desai, James & Ho 1984, p. 1160
  96. ^ Stein 1983, p. 165
  97. ^ Engesser & Krossing 2013, p. 947
  98. ^ Schweitzer & Pesterfield 2010, p. 305
  99. ^ Rieck 1967, p. 97: Tungsten trioxide dissolves in hydrofluoric acid to give an oxyfluoride complex.
  100. ^ Wiberg 2001, p. 1279
  101. ^ Pyper, N. C. (2020-09-18). "Relativity and the periodic table". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences. 378 (2180): 20190305. Bibcode:2020RSPTA.37890305P. doi:10.1098/rsta.2019.0305. ISSN 1364-503X. PMID 32811360.
  102. ^ Power 2010; Crow 2013; Weetman & Inoue 2018
  103. ^ Encyclopaedia Britannica 2021
  104. ^ Royal Society of Chemistry 2021
  105. ^ a b Matson & Orbaek 2013, p. 203
  106. ^ Kernion & Mascetta 2019, p. 191; Cao et al. 2021, pp. 20–21; Hussain et al. 2023; also called "nonmetal halogens": Chambers & Holliday 1982, pp. 273–274; Bohlmann 1992, p. 213; Jentzsch & Matile 2015, p. 247 or "stable halogens": Vassilakis, Kalemos & Mavridis 2014, p. 1; Hanley & Koga 2018, p. 24; Kaiho 2017, ch. 2, p. 1
  107. ^ Williams 2007, pp. 1550–1561: H, C, N, P, O, S
  108. ^ Wächtershäuser 2014, p. 5: H, C, N, P, O, S, Se
  109. ^ Hengeveld & Fedonkin 2007, pp. 181–226: C, N, P, O, S
  110. ^ Wakeman 1899, p. 562
  111. ^ Fraps 1913, p. 11: H, C, Si, N, P, O, S, Cl
  112. ^ Parameswaran at al. 2020, p. 210: H, C, N, P, O, S, Se
  113. ^ Knight 2002, p. 148: H, C, N, P, O, S, Se
  114. ^ Fraústo da Silva & Williams 2001, p. 500: H, C, N, O, S, Se
  115. ^ Zhu et al. 2022
  116. ^ Graves 2022
  117. ^ Rosenberg 2013, p. 847
  118. ^ Obodovskiy 2015, p. 151
  119. ^ Greenwood & Earnshaw 2002, p. 552
  120. ^ Eagleson 1994, p. 91
  121. ^ Huang 2018, pp. 30, 32
  122. ^ Orisakwe 2012, p. 000
  123. ^ Yin et al. 2018, p. 2
  124. ^ a b Moeller et al. 1989, p. 742
  125. ^ Whiteford & Coffin 1939, p. 239
  126. ^ a b Jones 2010, pp. 169–71
  127. ^ Russell & Lee 2005, p. 419
  128. ^ Tyler 1948, p. 105; Reilly 2002, pp. 5–6
  129. ^ Jolly 1966, p. 20
  130. ^ Clugston & Flemming 2000, pp. 100–101, 104–105, 302
  131. ^ Maosheng 2020, p. 962
  132. ^ Mazej 2020
  133. ^ Wiberg 2001, p. 402
  134. ^ Rudolph 1973, p. 133: "Oxygen and the halogens in particular ... are therefore strong oxidizing agents."
  135. ^ Daniel & Rapp 1976, p. 55
  136. ^ a b Cotton et al. 1999, p. 554
  137. ^ Woodward et al. 1999, pp. 133–194
  138. ^ Phillips & Williams 1965, pp. 478–479
  139. ^ Moeller et al. 1989, p. 314
  140. ^ Lanford 1959, p. 176
  141. ^ Emsley 2011, p. 478
  142. ^ Seese & Daub 1985, p. 65
  143. ^ MacKay, MacKay & Henderson 2002, pp. 209, 211
  144. ^ Cousins, Davidson & García-Vivó 2013, pp. 11809–11811
  145. ^ a b Cao et al. 2021, p. 4
  146. ^ Liptrot 1983, p. 161; Malone & Dolter 2008, p. 255
  147. ^ Wiberg 2001, pp. 255–257
  148. ^ Scott & Kanda 1962, p. 153
  149. ^ Taylor 1960, p. 316
  150. ^ a b Emsley 2011, passim
  151. ^ Crawford 1968, p. 540; Benner, Ricardo & Carrigan 2018, pp. 167–168: "The stability of the carbon-carbon bond ... has made it the first choice element to scaffold biomolecules. Hydrogen is needed for many reasons; at the very least, it terminates C-C chains. Heteroatoms (atoms that are neither carbon nor hydrogen) determine the reactivity of carbon-scaffolded biomolecules. In ... life, these are oxygen, nitrogen and, to a lesser extent, sulfur, phosphorus, selenium, and an occasional halogen."
  152. ^ a b c Cao et al. 2021, p. 20
  153. ^ Zhao, Tu & Chan 2021
  154. ^ Wasewar 2021, pp. 322–323
  155. ^ Messler 2011, p. 10
  156. ^ King 1994, p. 1344; Powell & Tims 1974, pp. 189–191; Cao et al. 2021, pp. 20–21
  157. ^ Vernon 2020, pp. 221–223; Rayner-Canham 2020, p. 216
  158. ^ Chandra X-ray Center 2018
  159. ^ Chapin, Matson & Vitousek 2011, p. 27
  160. ^ a b Fortescue 1980, p. 56
  161. ^ Georgievskii 1982, p. 58
  162. ^ Pepin, R. O.; Porcelli, D. (2002-01-01). "Origin of Noble Gases in the Terrestrial Planets". Reviews in Mineralogy and Geochemistry. 47 (1): 191–246. Bibcode:2002RvMG...47..191P. doi:10.2138/rmg.2002.47.7. ISSN 1529-6466.
  163. ^ Zhu et al. 2014, pp. 644–648
  164. ^ Klein & Dutrow 2007, p. 435[broken anchor]
  165. ^ Cockell 2019, p. 212, 208–211
  166. ^ Emsley 2011, pp. 363, 379
  167. ^ Emsley 2011, p. 516
  168. ^ Schmedt, Mangstl & Kraus 2012, p. 7847‒7849
  169. ^ Emsley 2011, pp. 39, 44, 80–81, 85, 199, 248, 263, 367, 478, 531, 610; Smulders 2011, pp. 416–421; Chen 1990, part 17.2.1; Hall 2021, p. 143: H (primary constituent of water); He (party balloons); B (in detergents); C (in pencils, as graphite); N (beer widgets); O (as peroxide, in detergents); F (as fluoride, in toothpaste); Ne (lighting); Si (in glassware); P (matches); S (garden treatments); Cl (bleach constituent); Ar (insulated windows); Ge (in wide-angle camera lenses); Se (glass; solar cells); Br (as bromide, for purification of spa water); Kr (energy saving fluorescent lamps); Sb (in batteries); Te (in ceramics, solar panels, rewrite-able DVDs); I (in antiseptic solutions); Xe (in plasma TV display cells, a technology subsequently made redundant by low cost LED and OLED displays.
  170. ^ Maroni 1995, pp. 108–123
  171. ^ Imbertierti 2020: H, He, B, C, N, O, F, Si, P, S, Cl, Ar, As, Se, Br, Kr, Sb, Te, I, Xe and Rn
  172. ^ Csele 2016; Winstel 2000; Davis et al. 2006, p. 431–432; Grondzik et al. 2010, p. 561: Cl, Ar, Ge, As, Se, Br, Kr, Te, I and Xe
  173. ^ Oxford English Dictionary; Eagleson 1994 (all bar germanic acid); Wiberg 2001, p. 897, germanic acid: H, B, C, N, O, F, Si, P, S, Cl, Ge, As, Sb, Br, Te, I and Xe
  174. ^ Bhuwalka et al. 2021, pp. 10097–10107: H, He, B, C, N, O, F, Si, P, S, Cl, Ar, Br, Sb, Te and I
  175. ^ King 2019, p. 408: H, He, B, C, N, O, F, Si, P, S, Cl, Ge, As, Se, Br, Sb
  176. ^ Emsley 2011, pp. 98, 117, 331, 487; Gresham et al. 2015, pp. 25, 55, 60, 63: H, He, B, C, N, O, F, Si, P, S, Cl, Ar, Se, Sb
  177. ^ Beard et al. 2021; Slye 2008: H, B, C (including graphite), N, O, F, Si, P, S, Cl, Ar, Br and Sb
  178. ^ Reinhardt at al. 2015; Eagleson 1994, p. 1053: H, He, C, N, O, F, P, S and Ar
  179. ^ Windmeier & Barron 2013: H, He, N, O, F, Ne, S, Cl and Ar
  180. ^ Kiiski et al. 2016: H, B, C, N, O, Si, P, S
  181. ^ Emsley 2011, pp. 113, 231, 327, 362, 377, 393, 515:: H, C, N, O, P, S, Cl
  182. ^ Brandt & Weiler 2000: H, He, C, N, O, Ar
  183. ^ Harbison, Bourgeois & Johnson 2015, p. 364
  184. ^ Bolin 2017, p. 2-1
  185. ^ Jordan 2016
  186. ^ Stillman 1924, p. 213
  187. ^ de L'Aunay 1566, p. 7
  188. ^ Lémery 1699, p. 118; Dejonghe 1998, p. 329
  189. ^ Lavoisier 1790, p. 175
  190. ^ Strathern 2000, p. 239
  191. ^ Moore, F. J.; Hall, William T. (1918). A History Of Chemistry. McGraw-Hill. p. 99. Retrieved 2024-08-01. Lavoisier's Table is reproduced on page 99.
  192. ^ Criswell 2007, p. 1140
  193. ^ Salzberg 1991, p. 204
  194. ^ Friend JN 1953, Man and the Chemical Elements, 1st ed., Charles Scribner's Sons, New York
  195. ^ Berzelius 1811, p. 258
  196. ^ Partington 1964, p. 168
  197. ^ a b Bache 1832, p. 250
  198. ^ Apjohn, J. (1864). Manual of the Metalloids. United Kingdom: Longman.
  199. ^ a b c The Chemical News and Journal of Physical Science 1864
  200. ^ Goldsmith 1982, p. 526
  201. ^ Roscoe & Schormlemmer 1894, p. 4
  202. ^ Glinka 1960, p. 76
  203. ^ Hérold 2006, pp. 149–150
  204. ^ Oxford English Dictionary 1989
  205. ^ Kemshead 1875, p. 13
  206. ^ Bertomeu-Sánchez et al. 2002, pp. 248–249
  207. ^ Dupasquier 1844, pp. 66–67
  208. ^ Bache 1832, pp. 248–276
  209. ^ Renouf 1901, pp. 268
  210. ^ Bertomeu-Sánchez et al. 2002, p. 248
  211. ^ Bertomeu-Sánchez et al. 2002, p. 236
  212. ^ Hoefer 1845, p. 85
  213. ^ Dumas 1828; Dumas 1859
  214. ^ a b Harris 1803, p. 274
  215. ^ Smith 1906, pp. 646–647
  216. ^ Beach 1911
  217. ^ Edwards & Sienko 1983, p. 693
  218. ^ Herzfeld 1927; Edwards 2000, pp. 100–103
  219. ^ a b Edwards 2010, pp. 941–965
  220. ^ Kubaschewski 1949, pp. 931–940
  221. ^ Butera, Richard A.; Waldeck, David H. (September 1997). "The Dependence of Resistance on Temperature for Metals, Semiconductors, and Superconductors". Journal of Chemical Education. 74 (9): 1090. Bibcode:1997JChEd..74.1090B. doi:10.1021/ed074p1090. ISSN 0021-9584.
  222. ^ Stott 1956, pp. 100–102
  223. ^ White 1962, p. 106
  224. ^ Martin 1969, p. 6
  225. ^ Parish 1977, p. 178
  226. ^ Rao & Ganguly 1986
  227. ^ Smith & Dwyer 1991, p. 65
  228. ^ Scott 2001, p. 1781
  229. ^ Suresh & Koga 2001, pp. 5940–5944
  230. ^ Yao B, Kuznetsov VL, Xiao T, et al. (2020). "Metals and non-metals in the periodic table". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences. 378 (2180): 1–21. Bibcode:2020RSPTA.37800213Y. doi:10.1098/rsta.2020.0213. PMC 7435143. PMID 32811363.
  231. ^ David Knight (2004) "Davy, Sir Humphry, baronet (1778–1829)" Archived 24 September 2015 at the Wayback Machine in Oxford Dictionary of National Biography, Oxford University Press
  232. ^ Edwards 2000, p. 85
  233. ^ Johnson 1966, pp. 3–6, 15
  234. ^ Shkol'nikov 2010, p. 2127
  235. ^ Aylward & Findlay 2008, pp. 6–13; 126
  236. ^ a b Rahm, Zeng & Hoffmann 2019, p. 345
  237. ^ Duffus 2002, p. 798
  238. ^ Hein & Arena 2011, pp. 228, 523; Timberlake 1996, pp. 88, 142; Kneen, Rogers & Simpson 1972, p. 263; Baker 1962, pp. 21, 194; Moeller 1958, pp. 11, 178
  239. ^ Goldwhite & Spielman 1984, p. 130
  240. ^ Emsley 1971, p. 1
  241. ^ Oderberg 2007, p. 97
  242. ^ Kneen, Rogers & Simpson 1972, pp. 218–219
  243. ^ Herman 1999, p. 702
  244. ^ Russell & Lee 2005, p. 466
  245. ^ Atkins et al. 2006, pp. 320–21
  246. ^ Zhigal'skii & Jones 2003, p. 66
  247. ^ a b c Rochow 1966, p. 4
  248. ^ Wiberg 2001, p. 780; Emsley 2011, p. 397; Rochow 1966, pp. 23, 84
  249. ^ Kneen, Rogers & Simpson 1972, p. 439
  250. ^ Kneen, Rogers & Simpson 1972, pp. 321, 404, 436
  251. ^ Kneen, Rogers & Simpson 1972, p. 465
  252. ^ Kneen, Rogers & Simpson 1972, p. 308
  253. ^ Tregarthen 2003, p. 10
  254. ^ Lewis 1993, pp. 28, 827
  255. ^ Lewis 1993, pp. 28, 813
  256. ^ Chung 1987
  257. ^ Godfrin & Lauter 1995, pp. 216‒218
  258. ^ Janas, Cabrero-Vilatela & Bulmer 2013
  259. ^ Wiberg 2001, p. 416
  260. ^ Desai, James & Ho 1984, p. 1160; Matula 1979, p. 1260
  261. ^ Schaefer 1968, p. 76; Carapella 1968, pp. 29‒32
  262. ^ Greenwood & Earnshaw 2002, p. 804
  263. ^ Kneen, Rogers & Simpson 1972, p. 264
  264. ^ Rayner-Canham 2018, p. 203
  265. ^ Welcher 2009, p. 3–32: "The elements change from ... metalloids, to moderately active nonmetals, to very active nonmetals, and to a noble gas."
  266. ^ Mackin 2014, p. 80
  267. ^ Johnson 1966, pp. 105–108
  268. ^ Stein 1969, pp. 5396‒5397; Pitzer 1975, pp. 760‒761
  269. ^ Rochow 1966, p. 4; Atkins et al. 2006, pp. 8, 122–123
  270. ^ Wiberg 2001, p. 750.
  271. ^ Douglade & Mercier 1982, p. 723
  272. ^ Gillespie & Robinson 1959, p. 418
  273. ^ Sanderson 1967, p. 172; Mingos 2019, p. 27
  274. ^ House 2008, p. 441
  275. ^ Mingos 2019, p. 27; Sanderson 1967, p. 172
  276. ^ Wiberg 2001, p. 399
  277. ^ Kläning & Appelman 1988, p. 3760
  278. ^ a b Rao 2002, p. 22
  279. ^ Sidorov 1960, pp. 599–603
  280. ^ McMillan 2006, p. 823
  281. ^ Wells 1984, p. 534
  282. ^ a b Puddephatt & Monaghan 1989, p. 59
  283. ^ King 1995, p. 182
  284. ^ Ritter 2011, p. 10
  285. ^ Yamaguchi & Shirai 1996, p. 3
  286. ^ Vernon 2020, p. 223
  287. ^ Woodward et al. 1999, p. 134
  288. ^ Dalton 2019

Bibliography

[edit]
  • Abbott D 1966, An Introduction to the Periodic Table, J. M. Dent & Sons, London
  • Addison WE 1964, The Allotropy of the Elements, Oldbourne Press, London
  • Atkins PA et al. 2006, Shriver & Atkins' Inorganic Chemistry, 4th ed., Oxford University Press, Oxford, ISBN 978-0-7167-4878-6
  • Aylward G and Findlay T 2008, SI Chemical Data, 6th ed., John Wiley & Sons Australia, Milton, ISBN 978-0-470-81638-7
  • Bache AD 1832, "An essay on chemical nomenclature, prefixed to the treatise on chemistry; by J. J. Berzelius", American Journal of Science, vol. 22, pp. 248–277
  • Baker et al. PS 1962, Chemistry and You, Lyons and Carnahan, Chicago
  • Barton AFM 2021, States of Matter, States of Mind, CRC Press, Boca Raton, ISBN 978-0-7503-0418-4
  • Beach FC (ed.) 1911, The Americana: A universal reference library, vol. XIII, Mel–New, Metalloid, Scientific American Compiling Department, New York
  • Beard A, Battenberg, C & Sutker BJ 2021, "Flame retardants", in Ullmann's Encyclopedia of Industrial Chemistry, doi:10.1002/14356007.a11_123.pub2
  • Beiser A 1987, Concepts of modern physics, 4th ed., McGraw-Hill, New York, ISBN 978-0-07-004473-9
  • Benner SA, Ricardo A & Carrigan MA 2018, "Is there a common chemical model for life in the universe?", in Cleland CE & Bedau MA (eds.), The Nature of Life: Classical and Contemporary Perspectives from Philosophy and Science, Cambridge University Press, Cambridge, ISBN 978-1-108-72206-3
  • Benzhen et al. 2020, Metals and non-metals in the periodic table, Philosophical Transactions of the Royal Society A, vol. 378, 20200213
  • Berger LI 1997, Semiconductor Materials, CRC Press, Boca Raton, ISBN 978-0-8493-8912-2
  • Bertomeu-Sánchez JR, Garcia-Belmar A & Bensaude-Vincent B 2002, "Looking for an order of things: Textbooks and chemical classifications in nineteenth century France", Ambix, vol. 49, no. 3, doi:10.1179/amb.2002.49.3.227
  • Berzelius JJ 1811, 'Essai sur la nomenclature chimique', Journal de Physique, de Chimie, d'Histoire Naturelle, vol. LXXIII, pp. 253‒286
  • Bhuwalka et al. 2021, "Characterizing the changes in material use due to vehicle electrification", Environmental Science & Technology vol. 55, no. 14, doi:10.1021/acs.est.1c00970
  • Bogoroditskii NP & Pasynkov VV 1967, Radio and Electronic Materials, Iliffe Books, London
  • Bohlmann R 1992, "Synthesis of halides", in Winterfeldt E (ed.), Heteroatom manipulation, Pergamon Press, Oxford, ISBN 978-0-08-091249-3
  • Boreskov GK 2003, Heterogeneous Catalysis, Nova Science, New York, ISBN 978-1-59033-864-3
  • Brady JE & Senese F 2009, Chemistry: The study of Matter and its Changes, 5th ed., John Wiley & Sons, New York, ISBN 978-0-470-57642-7
  • Brande WT 1821, A Manual of Chemistry, vol. II, John Murray, London
  • Brandt HG & Weiler H, 2000, "Welding and cutting", in Ullmann's Encyclopedia of Industrial Chemistry, doi:10.1002/14356007.a28_203
  • Brannt WT 1919, Metal Worker's Handy-book of Receipts and Processes, HC Baird & Company, Philadelphia
  • Brown TL et al. 2014, Chemistry: The Central Science, 3rd ed., Pearson Australia: Sydney, ISBN 978-1-4425-5460-3
  • Burford N, Passmore J & Sanders JCP 1989, "The preparation, structure, and energetics of homopolyatomic cations of groups 16 (the chalcogens) and 17 (the halogens)", in Liebman JF & Greenberg A (eds.), From atoms to polymers: isoelectronic analogies, VCH, New York, ISBN 978-0-89573-711-3
  • Bynum WF, Browne J & Porter R 1981 (eds), Dictionary of the History of Science, Princeton University Press, Princeton, ISBN 978-0-691-08287-5
  • Cahn RW & Haasen P, Physical Metallurgy: Vol. 1, 4th ed., Elsevier Science, Amsterdam,ISBN 978-0-444-89875-3
  • Cao C et al. 2021, "Understanding periodic and non-periodic chemistry in periodic tables", Frontiers in Chemistry, vol. 8, no. 813, doi:10.3389/fchem.2020.00813
  • Carapella SC 1968, "Arsenic" in Hampel CA (ed.), The Encyclopedia of the Chemical Elements, Reinhold, New York
  • Carmalt CJ & Norman NC 1998, "Arsenic, antimony and bismuth: Some general properties and aspects of periodicity", in Norman NC (ed.), Chemistry of Arsenic, Antimony and Bismuth, Blackie Academic & Professional, London, pp. 1–38, ISBN 0-7514-0389-X
  • Carrasco et al. 2023, "Antimonene: a tuneable post-graphene material for advanced applications in optoelectronics, catalysis, energy and biomedicine", Chemical Society Reviews, vol. 52, no. 4, p. 1288–1330, doi:10.1039/d2cs00570k
  • Challoner J 2014, The Elements: The New Guide to the Building Blocks of our Universe, Carlton Publishing Group, ISBN 978-0-233-00436-5
  • Chambers E 1743, in "Metal", Cyclopedia: Or an Universal Dictionary of Arts and Sciences (etc.), vol. 2, D Midwinter, London
  • Chambers C & Holliday AK 1982, Inorganic Chemistry, Butterworth & Co., London, ISBN 978-0-408-10822-5
  • Chandra X-ray Observatory 2018, Abundance Pie Chart, accessed 26 October 2023
  • Chapin FS, Matson PA & Vitousek PM 2011, Earth's climate system, in Principles of Terrestrial Ecosystem Ecology, Springer, New York, ISBN 978-1-4419-9503-2
  • Charlier J-C, Gonze X, Michenaud J-P 1994, "First-principles study of the stacking effect on the electronic properties of graphite(s)", Carbon, vol. 32, no. 2, pp. 289–99, doi:10.1016/0008-6223(94)90192-9
  • Chedd G 1969, Half-way elements: The technology of metalloids, Double Day, Garden City, NY
  • Chemical Abstracts Service 2021, CAS REGISTRY database as of November 2, Case #01271182
  • Chen K 1990, Industrial Power Distribution and Illuminating Systems, Marcel Dekker, New York, ISBN 978-0-8247-8237-5
  • Chung DD 1987, "Review of exfoliated graphite", Journal of Materials Science, vol. 22, doi:10.1007/BF01132008
  • Clugston MJ & Flemming R 2000, Advanced Chemistry, Oxford University Press, Oxford, ISBN 978-0-19-914633-8
  • Cockell C 2019, The Equations of Life: How Physics Shapes Evolution, Atlantic Books, London, ISBN 978-1-78649-304-0
  • Cook CG 1923, Chemistry in Everyday Life: With Laboratory Manual, D Appleton, New York
  • Cotton A et al. 1999, Advanced Inorganic Chemistry, 6th ed., Wiley, New York, ISBN 978-0-471-19957-1
  • Cousins DM, Davidson MG & García-Vivó D 2013, "Unprecedented participation of a four-coordinate hydrogen atom in the cubane core of lithium and sodium phenolates", Chemical Communications, vol. 49, doi:10.1039/C3CC47393G
  • Cox PA 1997, The Elements: Their Origins, Abundance, and Distribution, Oxford University Press, Oxford, ISBN 978-0-19-855298-7
  • Cox T 2004, Inorganic Chemistry, 2nd ed., BIOS Scientific Publishers, London, ISBN 978-1-85996-289-3
  • Crawford FH 1968, Introduction to the Science of Physics, Harcourt, Brace & World, New York
  • Cressey D 2010, "Chemists re-define hydrogen bond" Archived 2019-01-24 at the Wayback Machine, Nature newsblog, accessed August 23, 2017
  • Crichton R 2012, Biological Inorganic Chemistry: A New Introduction to Molecular Structure and Function, 2nd ed., Elsevier, Amsterdam, ISBN 978-0-444-53783-6
  • Criswell B 2007, "Mistake of having students be Mendeleev for just a day", Journal of Chemical Education, vol. 84, no. 7, pp. 1140–1144, doi:10.1021/ed084p1140
  • Crow JM 2013, Main group renaissance, Chemistry World, 31 May, accessed 26 December 2023
  • Csele M 2016, Lasers, in Ullmann's Encyclopedia of Industrial Chemistry, doi:10.1002/14356007.a15_165.pub2
  • Dalton L 2019, "Argon reacts with nickel under pressure-cooker conditions", Chemical & Engineering News, accessed November 6, 2019
  • de Clave E 1651, Nouvelle Lumière philosophique des vrais principes et élémens de nature, et qualité d'iceux, contre l'opinion commune, Olivier de Varennes, Paris
  • Daniel PL & Rapp RA 1976, "Halogen corrosion of metals", in Fontana MG & Staehle RW (eds.), Advances in Corrosion Science and Technology, Springer, Boston, doi:10.1007/978-1-4615-9062-0_2
  • de L'Aunay L 1566, Responce au discours de maistre Iacques Grevin, docteur de Paris, qu'il a escript contre le livre de maistre Loys de l'Aunay, medecin en la Rochelle, touchant la faculté de l'antimoine (Response to the Speech of Master Jacques Grévin,... Which He Wrote Against the Book of Master Loys de L'Aunay,... Touching the Faculty of Antimony), De l'Imprimerie de Barthelemi Berton, La Rochelle
  • Davis et al. 2006, "Atomic iodine lasers", in Endo M & Walter RF (eds) 2006, Gas Lasers, CRC Press, Boca Raton, Florida, ISBN 978-0-470-19565-9
  • DeKock RL & Gray HB 1989, Chemical structure and bonding, University Science Books, Mill Valley, CA, ISBN 978-0-935702-61-3
  • Dejonghe L 1998, "Zinc–lead deposits of Belgium", Ore Geology Reviews, vol. 12, no. 5, 329–354, doi:10.1016/s0169-1368(98)00007-9
  • Desai PD, James HM & Ho CY 1984, "Electrical resistivity of aluminum and manganese", Journal of Physical and Chemical Reference Data, vol. 13, no. 4, doi:10.1063/1.555725
  • Donohue J 1982, The Structures of the Elements, Robert E. Krieger, Malabar, Florida, ISBN 978-0-89874-230-5
  • Dorsey MG 2023, Holding Their Breath: How the Allies Confronted the Threat of Chemical Warfare in World War II, Cornell University Press, Ithaca, New York, pp. 12–13, ISBN 978-1-5017-6837-8
  • Douglade J, Mercier R 1982, Structure cristalline et covalence des liaisons dans le sulfate d’arsenic(III), As2(SO4)3, Acta Crystallographica Section B, vol. 38, no, 3, 720–723, doi:10.1107/s056774088200394x
  • Du Y, Ouyang C, Shi S & Lei M 2010, Ab initio studies on atomic and electronic structures of black phosphorus, Journal of Applied Physics, vol. 107, no. 9, pp. 093718–1–4, doi:10.1063/1.3386509
  • Duffus JH 2002, " 'Heavy metals'—A meaningless term?", Pure and Applied Chemistry, vol. 74, no. 5, pp. 793–807, doi:10.1351/pac200274050793
  • Dumas JBA 1828, Traité de Chimie Appliquée aux Arts, Béchet Jeune, Paris
  • Dumas JBA 1859, Mémoire sur les Équivalents des Corps Simples, Mallet-Bachelier, Paris
  • Dupasquier A 1844, Traité élémentaire de chimie industrielle, Charles Savy Juene, Lyon
  • Eagleson M 1994, Concise Encyclopedia Chemistry, Walter de Gruyter, Berlin, ISBN 3-11-011451-8
  • Earl B & Wilford D 2021, Cambridge O Level Chemistry, Hodder Education, London, ISBN 978-1-3983-1059-9
  • Edwards PP 2000, "What, why and when is a metal?", in Hall N (ed.), The New Chemistry, Cambridge University, Cambridge, pp. 85–114, ISBN 978-0-521-45224-3
  • Edwards PP et al. 2010, "... a metal conducts and a non-metal doesn't", Philosophical Transactions of the Royal Society A, 2010, vol, 368, no. 1914, doi:10.1098/rsta.2009.0282
  • Edwards PP & Sienko MJ 1983, "On the occurrence of metallic character in the periodic table of the elements", Journal of Chemical Education, vol. 60, no. 9, doi:10.1021/ed060p691, PMID 25666074
  • Elliot A 1929, "The absorption band spectrum of chlorine", Proceedings of the Royal Society A, vol. 123, no. 792, pp. 629–644, doi:10.1098/rspa.1929.0088
  • Emsley J 1971, The Inorganic Chemistry of the Non-metals, Methuen Educational, London, ISBN 978-0-423-86120-4
  • Emsley J 2011, Nature's Building Blocks: An A–Z Guide to the Elements, Oxford University Press, Oxford, ISBN 978-0-19-850341-5
  • Encyclopaedia Britannica, 2021, Periodic table, accessed September 21, 2021
  • Engesser TA & Krossing I 2013, "Recent advances in the syntheses of homopolyatomic cations of the non metallic elements C, N, P, S, Cl, Br, I and Xe", Coordination Chemistry Reviews, vol. 257, nos. 5–6, pp. 946–955, doi:10.1016/j.ccr.2012.07.025
  • Erman P & Simon P 1808, "Third report of Prof. Erman and State Architect Simon on their joint experiments", Annalen der Physik, vol. 28, no. 3, pp. 347–367
  • Evans RC 1966, An Introduction to Crystal Chemistry, 2nd ed., Cambridge University, Cambridge
  • Faraday M 1853, The Subject Matter of a Course of Six Lectures on the Non-metallic Elements, (arranged by John Scoffern), Longman, Brown, Green, and Longmans, London
  • Field JE (ed.) 1979, The Properties of Diamond, Academic Press, London, ISBN 978-0-12-255350-9
  • Florez et al. 2022, "From the gas phase to the solid state: The chemical bonding in the superheavy element flerovium", The Journal of Chemical Physics, vol. 157, 064304, doi:10.1063/5.0097642
  • Fortescue JAC 2012, Environmental Geochemistry: A Holistic Approach, Springer-Verlag, New York, ISBN 978-1-4612-6047-9
  • Fox M 2010, Optical Properties of Solids, 2nd ed., Oxford University Press, New York, ISBN 978-0-19-957336-3
  • Fraps GS 1913, Principles of Agricultural Chemistry, The Chemical Publishing Company, Easton, PA
  • Fraústo da Silva JJR & Williams RJP 2001, The Biological Chemistry of the Elements: The Inorganic Chemistry of Life, 2nd ed., Oxford University Press, Oxford, ISBN 978-0-19-850848-9
  • Gaffney J & Marley N 2017, General Chemistry for Engineers, Elsevier, Amsterdam, ISBN 978-0-12-810444-6
  • Ganguly A 2012, Fundamentals of Inorganic Chemistry, 2nd ed., Dorling Kindersley (India), New Delhi ISBN 978-81-317-6649-1
  • Gargaud M et al. (eds.) 2006, Lectures in Astrobiology, vol. 1, part 1: The Early Earth and Other Cosmic Habitats for Life, Springer, Berlin, ISBN 978-3-540-29005-6
  • Gatti M, Tokatly IV & Rubio A, 2010, Sodium: a charge-transfer insulator at high pressures, Physical Review Letters, vol. 104, no. 21, doi:10.1103/PhysRevLett.104.216404
  • Georgievskii VI 1982, Mineral compositions of bodies and tissues of animals, in Georgievskii VI, Annenkov BN & Samokhin VT (eds), Mineral Nutrition of Animals: Studies in the Agricultural and Food Sciences, Butterworths, London, ISBN 978-0-408-10770-9
  • Gillespie RJ, Robinson EA 1959, The sulfuric acid solvent system, in Emeléus HJ, Sharpe AG (eds), Advances in Inorganic Chemistry and Radiochemistry, vol. 1, pp. 386–424, Academic Press, New York
  • Gillham EJ 1956, A semi-conducting antimony bolometer, Journal of Scientific Instruments, vol. 33, no. 9, doi:10.1088/0950-7671/33/9/303
  • Glinka N 1960, General chemistry, Sobolev D (trans.), Foreign Languages Publishing House, Moscow
  • Godfrin H & Lauter HJ 1995, "Experimental properties of 3He adsorbed on graphite", in Halperin WP (ed.), Progress in Low Temperature Physics, volume 14, Elsevier Science B.V., Amsterdam, ISBN 978-0-08-053993-5
  • Godovikov AA & Nenasheva N 2020, Structural-chemical Systematics of Minerals, 3rd ed., Springer, Cham, Switzerland, ISBN 978-3-319-72877-3
  • Goldsmith RH 1982, "Metalloids", Journal of Chemical Education, vol. 59, no. 6, pp. 526–527, doi:10.1021/ed059p526
  • Goldwhite H & Spielman JR 1984, College Chemistry, Harcourt Brace Jovanovich, San Diego, ISBN 978-0-15-601561-5
  • Goodrich BG 1844, A Glance at the Physical Sciences, Bradbury, Soden & Co., Boston
  • Gresham et al. 2015, Lubrication and lubricants, in Kirk-Othmer Encyclopedia of Chemical Technology, John Wiley & Sons, doi:10.1002/0471238961.1221021802151519.a01.pub3, accessed Jun 3, 2024
  • Grondzik WT et al. 2010, Mechanical and Electrical Equipment for Buildings, 11th ed., John Wiley & Sons, Hoboken, ISBN 978-0-470-19565-9
  • Government of Canada 2015, Periodic table of the elements, accessed August 30, 2015
  • Graves Jr JL 2022, A Voice in the Wilderness: A Pioneering Biologist Explains How Evolution Can Help Us Solve Our Biggest Problems, Basic Books, New York, ISBN 978-1-6686-1610-9,
  • Green D 2012, The Elements, Scholastic, Southam, Warwickshire, ISBN 978-1-4071-3155-9
  • Greenberg A 2007, From alchemy to chemistry in picture and story, John Wiley & Sons, Hoboken, NJ, 978-0-471-75154-0
  • Greenwood NN 2001, Main group element chemistry at the millennium, Journal of the Chemical Society, Dalton Transactions, no. 14, pp. 2055–66, doi:10.1039/b103917m
  • Greenwood NN & Earnshaw A 2002, Chemistry of the Elements, 2nd ed., Butterworth-Heinemann, ISBN 978-0-7506-3365-9
  • Grochala W 2018, "On the position of helium and neon in the Periodic Table of Elements", Foundations of Chemistry, vol. 20, pp. 191–207, doi:10.1007/s10698-017-9302-7
  • Hall RA 2021, Pop Goes the Decade: The 2000s, ABC-CLIO, Santa Barbara, California, ISBN 978-1-4408-6812-2
  • Haller EE 2006, "Germanium: From its discovery to SiGe devices", Materials Science in Semiconductor Processing, vol. 9, nos 4–5, accessed 9 October 2013
  • Hampel CA & Hawley GG 1976, Glossary of Chemical Terms, Van Nostrand Reinhold, New York, ISBN 978-0-442-23238-2
  • Hanley JJ & Koga KT 2018, "Halogens in terrestrial and cosmic geochemical systems: Abundances, geochemical behaviors, and analytical methods" in The Role of Halogens in Terrestrial and Extraterrestrial Geochemical Processes: Surface, Crust, and Mantle, Harlov DE & Aranovich L (eds.), Springer, Cham, ISBN 978-3-319-61667-4
  • Harbison RD, Bourgeois MM & Johnson GT 2015, Hamilton and Hardy's Industrial Toxicology, 6th ed., John Wiley & Sons, Hoboken, ISBN 978-0-470-92973-5
  • Hare RA & Bache F 1836, Compendium of the Course of Chemical Instruction in the Medical Department of the University of Pennsylvania, 3rd ed., JG Auner, Philadelphia
  • Harris TM 1803, The Minor Encyclopedia, vol. III, West & Greenleaf, Boston
  • Hein M & Arena S 2011, Foundations of College Chemistry, 13th ed., John Wiley & Sons, Hoboken, New Jersey, ISBN 978-0470-46061-0
  • Hengeveld R & Fedonkin MA 2007, "Bootstrapping the energy flow in the beginning of life", Acta Biotheoretica, vol. 55, doi:10.1007/s10441-007-9019-4
  • Herman ZS 1999, "The nature of the chemical bond in metals, alloys, and intermetallic compounds, according to Linus Pauling", in Maksić, ZB, Orville-Thomas WJ (eds.), 1999, Pauling's Legacy: Modern Modelling of the Chemical Bond, Elsevier, Amsterdam, doi:10.1016/S1380-7323(99)80030-2
  • Hermann A, Hoffmann R & Ashcroft NW 2013, "Condensed astatine: Monatomic and metallic", Physical Review Letters, vol. 111, doi:10.1103/PhysRevLett.111.116404
  • Hérold A 2006, "An arrangement of the chemical elements in several classes inside the periodic table according to their common properties", Comptes Rendus Chimie, vol. 9, no. 1, doi:10.1016/j.crci.2005.10.002
  • Herzfeld K 1927, "On atomic properties which make an element a metal", Physical Review, vol. 29, no. 5, doi:10.1103/PhysRev.29.701
  • Hill G, Holman J & Hulme PG 2017, Chemistry in Context, 7th ed., Oxford University Press, Oxford, ISBN 978-0-19-839618-5
  • Hoefer F 1845, Nomenclature et Classifications Chimiques, J.-B. Baillière, Paris
  • Holderness A & Berry M 1979, Advanced Level Inorganic Chemistry, 3rd ed., Heinemann Educational Books, London, ISBN 978-0-435-65435-1
  • Horvath AL 1973, "Critical temperature of elements and the periodic system", Journal of Chemical Education, vol. 50, no. 5, doi:10.1021/ed050p335
  • House JE 2008, Inorganic Chemistry, Elsevier, Amsterdam, ISBN 978-0-12-356786-4
  • House JE 2013, Inorganic Chemistry, 2nd ed., Elsevier, Kidlington, ISBN 978-0-12-385110-9
  • Huang Y 2018, Thermodynamics of materials corrosion, in Huang Y & Zhang J (eds), Materials Corrosion and Protection, De Gruyter, Boston, pp. 25–58, doi:10.1515/9783110310054-002
  • Humphrey TPJ 1908, "Systematic course of study, Chemistry and physics", Pharmaceutical Journal, vol. 80, p. 58
  • Hussain et al. 2023, "Tuning the electronic properties of molybdenum di-sulphide monolayers via doping using first-principles calculations", Physica Scripta, vol. 98, no. 2, doi:10.1088/1402-4896/acacd1
  • Imberti C & Sadler PJ, 2020, "150 years of the periodic table: New medicines and diagnostic agents", in Sadler PJ & van Eldik R 2020, Advances in Inorganic Chemistry, vol. 75, Academic Press, ISBN 978-0-12-819196-5
  • IUPAC Periodic Table of the Elements, accessed October 11, 2021
  • Janas D, Cabrero-Vilatela, A & Bulmer J 2013, "Carbon nanotube wires for high-temperature performance", Carbon, vol. 64, pp. 305–314, doi:10.1016/j.carbon.2013.07.067
  • Jenkins GM & Kawamura K 1976, Polymeric Carbons—Carbon Fibre, Glass and Char, Cambridge University Press, Cambridge, ISBN 978-0-521-20693-8
  • Jentzsch AV & Matile S 2015, "Anion transport with halogen bonds", in Metrangolo P & Resnati G (eds.), Halogen Bonding I: Impact on Materials Chemistry and Life Sciences, Springer, Cham, ISBN 978-3-319-14057-5
  • Jensen WB 1986, Classification, symmetry and the periodic table, Computers & Mathematics with Applications, vol. 12B, nos. 1/2, pp. 487−510, doi:10.1016/0898-1221(86)90167-7
  • Johnson RC 1966, Introductory Descriptive Chemistry, WA Benjamin, New York
  • Jolly WL 1966, The Chemistry of the Non-metals, Prentice-Hall, Englewood Cliffs, New Jersey
  • Jones BW 2010, Pluto: Sentinel of the Outer Solar System, Cambridge University, Cambridge, ISBN 978-0-521-19436-5
  • Jordan JM 2016 " 'Ancient episteme' and the nature of fossils: a correction of a modern scholarly error", History and Philosophy of the Life Sciences, vol. 38, no, 1, pp. 90–116, doi:10.1007/s40656-015-0094-6
  • Kaiho T 2017, Iodine Made Simple, CRC Press, e-book, doi:10.1201/9781315158310
  • Keeler J & Wothers P 2013, Chemical Structure and Reactivity: An Integrated Approach, Oxford University Press, Oxford, ISBN 978-0-19-960413-5
  • Kemshead WB 1875, Inorganic chemistry, William Collins, Sons, & Company, London
  • Kernion MC & Mascetta JA 2019, Chemistry: The Easy Way, 6th ed., Kaplan, New York, ISBN 978-1-4380-1210-0
  • King AH 2019, "Our elemental footprint", Nature Materials, vol. 18, doi:10.1038/s41563-019-0334-3
  • King RB 1994, Encyclopedia of Inorganic Chemistry, vol. 3, John Wiley & Sons, New York, ISBN 978-0-471-93620-6
  • King RB 1995, Inorganic Chemistry of Main Group Elements, VCH, New York, ISBN 978-1-56081-679-9
  • Kiiski et al. 2016, "Fertilizers, 1. General", in Ullmann's Encyclopedia of Industrial Chemistry, doi:10.1002/14356007.a10_323.pub4
  • Kläning UK & Appelman EH 1988, "Protolytic properties of perxenic acid", Inorganic Chemistry, vol. 27, no. 21, doi:10.1021/ic00294a018
  • Kneen WR, Rogers MJW & Simpson P 1972, Chemistry: Facts, Patterns, and Principles, Addison-Wesley, London, ISBN 978-0-201-03779-1
  • Knight J 2002, Science of Everyday Things: Real-life chemistry, Gale Group, Detroit, ISBN 9780787656324
  • Koenig SH 1962, in Proceedings of the International Conference on the Physics of Semiconductors, held at Exeter, July 16–20, 1962, The Institute of Physics and the Physical Society, London
  • Kosanke et al. 2012, Encyclopedic Dictionary of Pyrotechnics (and Related Subjects), Part 3 – P to Z, Pyrotechnic Reference Series No. 5, Journal of Pyrotechnics, Whitewater, Colorado, ISBN 978-1-889526-21-8
  • Kubaschewski O 1949, "The change of entropy, volume and binding state of the elements on melting", Transactions of the Faraday Society, vol. 45, doi:10.1039/TF9494500931
  • Labinger JA 2019, "The history (and pre-history) of the discovery and chemistry of the noble gases", in Giunta CJ, Mainz VV & Girolami GS (eds.), 150 Years of the Periodic Table: A Commemorative Symposium, Springer Nature, Cham, Switzerland, ISBN 978-3-030-67910-1
  • Lanford OE 1959, Using Chemistry, McGraw-Hill, New York
  • Larrañaga MD, Lewis RJ & Lewis RA 2016, Hawley's Condensed Chemical Dictionary, 16th ed., Wiley, Hoboken, New York, ISBN 978-1-118-13515-0
  • Lavoisier A 1790, Elements of Chemistry, R Kerr (trans.), William Creech, Edinburgh
  • Lee JD 1996, Concise Inorganic Chemistry, 5th ed., Blackwell Science, Oxford, ISBN 978-0-632-05293-6
  • Lémery N 1699, Traité universel des drogues simples, mises en ordre alphabetique, L d'Houry, Paris, p. 118
  • Lewis RJ 1993, Hawley's Condensed Chemical Dictionary, 12th ed., Van Nostrand Reinhold, New York, ISBN 978-0-442-01131-4
  • Lewis RS & Deen WM 1994, "Kinetics of the reaction of nitric oxide with oxygen in aqueous solutions", Chemical Research in Toxicology, vol. 7, no. 4, pp. 568–574, doi:10.1021/tx00040a013
  • Liptrot GF 1983, Modern Inorganic Chemistry, 4th ed., Bell & Hyman, ISBN 978-0-7135-1357-8
  • Los Alamos National Laboratory 2021, Periodic Table of Elements: A Resource for Elementary, Middle School, and High School Students, accessed September 19, 2021
  • Lundgren A & Bensaude-Vincent B 2000, Communicating chemistry: textbooks and their audiences, 1789–1939, Science History, Canton, MA, ISBN 0-88135-274-8
  • MacKay KM, MacKay RA & Henderson W 2002, Introduction to Modern Inorganic Chemistry, 6th ed., Nelson Thornes, Cheltenham, ISBN 978-0-7487-6420-4
  • Mackin M 2014, Study Guide to Accompany Basics for Chemistry, Elsevier Science, Saint Louis, ISBN 978-0-323-14652-4
  • Malone LJ & Dolter T 2008, Basic Concepts of Chemistry, 8th ed., John Wiley & Sons, Hoboken, ISBN 978-0-471-74154-1
  • Mann et al. 2000, Configuration energies of the d-block elements, Journal of the American Chemical Society, vol. 122, no. 21, pp. 5132–5137, doi:10.1021/ja9928677
  • Maosheng M 2020, "Noble gases in solid compounds show a rich display of chemistry with enough pressure", Frontiers in Chemistry, vol. 8, doi:10.3389/fchem.2020.570492
  • Maroni M, Seifert B & Lindvall T (eds) 1995, "Physical pollutants", in Indoor Air Quality: A Comprehensive Reference Book, Elsevier, Amsterdam, ISBN 978-0-444-81642-9
  • Martin JW 1969, Elementary Science of Metals, Wykeham Publications, London
  • Matson M & Orbaek AW 2013, Inorganic Chemistry for Dummies, John Wiley & Sons: Hoboken, ISBN 978-1-118-21794-8
  • Matula RA 1979, "Electrical resistivity of copper, gold, palladium, and silver", Journal of Physical and Chemical Reference Data, vol. 8, no. 4, doi:10.1063/1.555614
  • Mazej Z 2020, "Noble-gas chemistry more than half a century after the first report of the noble-gas compound", Molecules, vol. 25, no. 13, doi:10.3390/molecules25133014, PMID 32630333, PMC 7412050
  • McMillan P 2006, "A glass of carbon dioxide", Nature, vol. 441, doi:10.1038/441823a
  • Mendeléeff DI 1897, The Principles of Chemistry, vol. 2, 5th ed., trans. G Kamensky, AJ Greenaway (ed.), Longmans, Green & Co., London
  • Messler Jr RW 2011, The Essence of Materials for Engineers, Jones and Bartlett Learning, Sudbury, Massachusetts, ISBN 978-0-7637-7833-0
  • Mewes et al. 2019, "Copernicium: A relativistic noble liquid", Angewandte Chemie International Edition, vol. 58, pp. 17964–17968, doi:10.1002/anie.201906966
  • Mingos DMP 2019, "The discovery of the elements in the Periodic Table", in Mingos DMP (ed.), The Periodic Table I. Structure and Bonding, Springer Nature, Cham, doi:10.1007/978-3-030-40025-5
  • Moeller T 1958, Qualitative Analysis: An Introduction to Equilibrium and Solution Chemistry, McGraw-Hill, New York
  • Moeller T et al. 1989, Chemistry: With Inorganic Qualitative Analysis, 3rd ed., Academic Press, New York, ISBN 978-0-12-503350-3
  • Moody B 1991, Comparative Inorganic Chemistry, 3rd ed., Edward Arnold, London, ISBN 978-0-7131-3679-1
  • Moore JT 2016, Chemistry for Dummies, 2nd ed., ch. 16, Tracking periodic trends, John Wiley & Sons: Hoboken, ISBN 978-1-119-29728-4
  • Morely HF & Muir MM 1892, Watt's Dictionary of Chemistry, vol. 3, Longman's Green, and Co., London
  • Moss, TS 1952, Photoconductivity in the Elements, Butterworths Scientific, London
  • Myers RT 1979, "Physical and chemical properties and bonding of metallic elements", Journal of Chemical Education, vol. 56, no. 11, pp. 712–73, doi:10.1021/ed056p71
  • Obodovskiy I 2015, Fundamentals of Radiation and Chemical Safety, Elsevier, Amsterdam, ISBN 978-0-12-802026-5
  • Oderberg DS 2007, Real Essentialism, Routledge, New York, ISBN 978-1-134-34885-5
  • Ostriker JP & Steinhardt PJ 2001, "The quintessential universe", Scientific American, vol. 284, no. 1, pp. 46–53 PMID 11132422, doi:10.1038/scientificamerican0101-46
  • Oxford English Dictionary 1989, "nonmetal"
  • Orisakwe OE 2012, Other heavy metals: antimony, cadmium, chromium and mercury, in Pacheco-Torgal F, Jalali S & Fucic A (eds), Toxicity of Building Materials, Woodhead Publishing, Oxford, pp. 297–333, doi:10.1533/9780857096357.297
  • Parameswaran P et al. 2020, "Phase evolution and characterization of mechanically alloyed hexanary Al16.6Mg16.6Ni16.6Cr16.6Ti16.6Mn16.6 high entropy alloy", Metal Powder Report, vol. 75, no. 4, doi:10.1016/j.mprp.2019.08.001
  • Parish RV 1977, The Metallic Elements, Longman, London, ISBN 978-0-582-44278-8
  • Partington JR 1944, A Text-book of Inorganic Chemistry, 5th ed., Macmillan & Co., London
  • Partington JR 1964, A history of chemistry, vol. 4, Macmillan, London
  • Pascoe KJ 1982, An Introduction to the Properties of Engineering Materials, 3rd ed., Von Nostrand Reinhold (UK), Wokingham, Berkshire, ISBN 978-0-442-30233-7
  • Pauling L 1947, General chemistry: An introduction to descriptive chemistry and modern chemical theory, WH Freeman, San Francisco
  • Pawlicki T, Scanderbeg DJ & Starkschall G 2016, Hendee's Radiation Therapy Physics, 4th ed., John Wiley & Sons, Hoboken, NJ, p. 228, ISBN 978-0-470-37651-5
  • Petruševski VM & Cvetković J 2018, "On the 'true position' of hydrogen in the Periodic Table", Foundations of Chemistry, vol. 20, pp. 251–260, doi:10.1007/s10698-018-9306-y
  • Phillips CSG & Williams RJP 1965, Inorganic Chemistry, vol. 1, Principles and non-metals, Clarendon Press, Oxford
  • Pitzer K 1975, "Fluorides of radon and elements 118", Journal of the Chemical Society, Chemical Communications, no. 18, doi:10.1039/C3975000760B
  • Porterfield WW 1993, Inorganic Chemistry, Academic Press, San Diego, ISBN 978-0-12-562980-5
  • Povh B & Rosina M 2017, Scattering and Structures: Essentials and Analogies in Quantum Physics, 2nd ed., Springer, Berlin, doi:10.1007/978-3-662-54515-7
  • Powell P & Timms P 1974, The Chemistry of the Non-Metals, Chapman and Hall, London, ISBN 978-0-412-12200-2
  • Power PP 2010, Main-group elements as transition metals, Nature, vol. 463, 14 January 2010, pp. 171–177, doi:10.1038/nature08634
  • Puddephatt RJ & Monaghan PK 1989, The Periodic Table of the Elements, 2nd ed., Clarendon Press, Oxford, ISBN 978-0-19-855516-2
  • Rahm M, Zeng T & Hoffmann R 2019, "Electronegativity seen as the ground-state average valence electron binding energy", Journal of the American Chemical Society, vol. 141, no. 1, pp. 342–351, doi:10.1021/jacs.8b10246
  • Ramdohr P 1969, The Ore Minerals and Their Intergrowths, Pergamon Press, Oxford
  • Rao CNR & Ganguly PA 1986, "New criterion for the metallicity of elements", Solid State Communications, vol. 57, no. 1, pp. 5–6, doi:10.1016/0038-1098(86)90659-9
  • Rao KY 2002, Structural chemistry of glasses, Elsevier, Oxford, ISBN 0-08-043958-6
  • Rayner-Canham G 2018, "Organizing the transition metals", in Scerri E & Restrepo G (Ed's.) Mendeleev to Oganesson: A multidisciplinary perspective on the periodic table, Oxford University, New York, ISBN 978-0-190-668532
  • Rayner-Canham G 2020, The Periodic Table: Past, Present and Future, World Scientific, New Jersey, ISBN 978-981-121-850-7
  • Redmer R, Hensel F & Holst B (eds) 2010, "Metal-to-Nonmetal Transitions", Springer, Berlin, ISBN 978-3-642-03952-2
  • Regnault MV 1853, Elements of Chemistry, vol. 1, 2nd ed., Clark & Hesser, Philadelphia
  • Reilly C 2002, Metal Contamination of Food, Blackwell Science, Oxford, ISBN 978-0-632-05927-0
  • Reinhardt et al. 2015, Inerting in the chemical industry, Linde, Pullach, Germany, accessed October 19, 2021
  • Remy H 1956, Treatise on Inorganic Chemistry, Anderson JS (trans.), Kleinberg J (ed.), vol. II, Elsevier, Amsterdam
  • Renouf E 1901, "Lehrbuch der Anorganischen Chemie", Science, vol. 13, no. 320, doi:10.1126/science.13.320.268
  • Restrepo G, Llanos EJ & Mesa H 2006, "Topological space of the chemical elements and its properties", Journal of Mathematical Chemistry, vol. 39, doi:10.1007/s10910-005-9041-1
  • Rieck GD 1967, Tungsten and its Compounds, Pergamon Press, Oxford
  • Ritter SK 2011, "The case of the missing xenon", Chemical & Engineering News, vol. 89, no. 9, ISSN 0009-2347
  • Rochow EG 1966, The Metalloids, DC Heath and Company, Boston
  • Rosenberg E 2013, Germanium-containing compounds, current knowledge and applications, in Kretsinger RH, Uversky VN & Permyakov EA (eds), Encyclopedia of Metalloproteins, Springer, New York, doi:10.1007/978-1-4614-1533-6_582
  • Roscoe HE & Schorlemmer FRS 1894, A Treatise on Chemistry: Volume II: The Metals, D Appleton, New York
  • Royal Society of Chemistry 2021, Periodic Table: Non-metal, accessed September 3, 2021
  • Rudakiya DM & Patel Y 2021, Bioremediation of metals, metalloids, and nonmetals, in Panpatte DG & Jhala YK (eds), Microbial Rejuvenation of Polluted Environment, vol. 2, Springer Nature, Singapore, pp. 33–49, doi:10.1007/978-981-15-7455-9_2
  • Rudolph J 1973, Chemistry for the Modern Mind, Macmillan, New York
  • Russell AM & Lee KL 2005, Structure-Property Relations in Nonferrous Metals, Wiley-Interscience, New York, ISBN 0-471-64952-X
  • Salinas JT 2019 Exploring Physical Science in the Laboratory, Moreton Publishing, Englewood, Colorado, ISBN 978-1-61731-753-8
  • Salzberg HW 1991, From Caveman to Chemist: Circumstances and Achievements, American Chemical Society, Washington, DC, ISBN 0-8412-1786-6
  • Sanderson RT 1967, Inorganic Chemistry, Reinhold, New York
  • Scerri E (ed.) 2013, 30-Second Elements: The 50 Most Significant Elements, Each Explained In Half a Minute, Ivy Press, London, ISBN 978-1-84831-616-4
  • Scerri E 2020, The Periodic Table: Its Story and Its Significance, Oxford University Press, New York, ISBN 978-0-19091-436-3
  • Schaefer JC 1968, "Boron" in Hampel CA (ed.), The Encyclopedia of the Chemical Elements, Reinhold, New York
  • Schmedt auf der Günne J, Mangstl M & Kraus F 2012, "Occurrence of difluorine F2 in nature—In situ proof and quantification by NMR spectroscopy", Angewandte Chemie International Edition, vol. 51, no. 31, doi:10.1002/anie.201203515
  • Schweitzer GK & Pesterfield LL 2010, Aqueous Chemistry of the Elements, Oxford University Press, Oxford, ISBN 978-0-19-539335-4
  • Scott D 2014, Around the World in 18 Elements, Royal Society of Chemistry, e-book, ISBN 978-1-78262-509-4
  • Scott EC & Kanda FA 1962, The Nature of Atoms and Molecules: A General Chemistry, Harper & Row, New York
  • Scott WAH 2001, Chemistry Basic Facts, 5th ed., HarperCollins, Glasgow, ISBN 978-0-00-710321-8
  • Seese WS & Daub GH 1985, Basic Chemistry, 4th ed., Prentice-Hall, Englewood Cliffs, NJ, ISBN 978-0-13-057811-2
  • Segal BG 1989, Chemistry: Experiment and Theory, 2nd ed., John Wiley & Sons, New York, ISBN 0-471-84929-4
  • Shanabrook BV, Lannin JS & Hisatsune IC 1981, "Inelastic light scattering in a onefold-coordinated amorphous semiconductor", Physical Review Letters, vol. 46, no. 2, 12 January, doi:10.1103/PhysRevLett.46.130
  • Shang et al. 2021, "Ultrahard bulk amorphous carbon from collapsed fullerene", Nature, vol. 599, pp. 599–604, doi:10.1038/s41586-021-03882-9
  • Shchukarev SA 1977, New views of D. I. Mendeleev's system. I. Periodicity of the stratigraphy of atomic electronic shells in the system, and the concept of Kainosymmetry", Zhurnal Obshchei Kimii, vol. 47, no. 2, pp. 246–259
  • Shkol’nikov EV 2010, "Thermodynamic characterization of the amphoterism of oxides M2O3 (M = AS, Sb, Bi) and their hydrates in aqueous media, Russian Journal of Applied Chemistry, vol. 83, no. 12, pp. 2121–2127, doi:10.1134/S1070427210120104
  • Sidorov TA 1960, "The connection between structural oxides and their tendency to glass formation", Glass and Ceramics, vol. 17, no. 11, doi:10.1007BF00670116
  • Siekierski S & Burgess J 2002, Concise Chemistry of the Elements, Horwood Press, Chichester, ISBN 978-1-898563-71-6
  • Slye OM Jr 2008, "Fire extinguishing agents", in Ullmann's Encyclopedia of Industrial Chemistry, doi:10.1002/14356007.a11_113.pub2
  • Smith A 1906, Introduction to Inorganic Chemistry, The Century Co., New York
  • Smith A & Dwyer C 1991, Key Chemistry: Investigating Chemistry in the Contemporary World: Book 1: Materials and Everyday Life, Melbourne University Press, Carlton, Victoria, ISBN 978-0-522-84450-4
  • Smith DW 1990, Inorganic Substances: A Prelude to the Study of Descriptive Chemistry, Cambridge University Press, Cambridge, ISBN 978-0-521-33136-4
  • Smits et al. 2020, "Oganesson: A noble gas element that is neither noble nor a gas", Angewandte Chemie International Edition, vol. 59, pp. 23636–23640, doi:10.1002/anie.202011976
  • Smulders E & Sung E 2011, "Laundry Detergents, 2, Ingredients and Products’’, In Ullmann's Encyclopedia of Industrial Chemistry, doi:10.1002/14356007.o15_o13
  • Spencer JN, Bodner GM, Rickard LY 2012, Chemistry: Structure & Dynamics, 5th ed., John Wiley & Sons, Hoboken, ISBN 978-0-470-58711-9
  • Stein L 1969, "Oxidized radon in halogen fluoride solutions", Journal of the American Chemical Society, vol. 19, no. 19, doi:10.1021/ja01047a042
  • Stein L 1983, "The chemistry of radon", Radiochimica Acta, vol. 32, doi:10.1524/ract.1983.32.13.163
  • Steudel R 2020, Chemistry of the Non-metals: Syntheses – Structures – Bonding – Applications, in collaboration with D Scheschkewitz, Berlin, Walter de Gruyter, doi:10.1515/9783110578065
  • Still B 2016 The Secret Life of the Periodic Table, Cassell, London, ISBN 978-1-84403-885-5
  • Stillman JM 1924, The Story of Early Chemistry, D. Appleton, New York
  • Stott RWA 1956, Companion to Physical and Inorganic Chemistry, Longmans, Green and Co, London
  • Stuke J 1974, "Optical and electrical properties of selenium", in Zingaro RA & Cooper WC (eds.), Selenium, Van Nostrand Reinhold, New York, pp. 174
  • Strathern P 2000, Mendeleyev's dream: The Quest for the Elements, Hamish Hamilton, London, ISBN 9780425184677
  • Suresh CH & Koga NA 2001, "A consistent approach toward atomic radii”, Journal of Physical Chemistry A, vol. 105, no. 24. doi:10.1021/jp010432b
  • Tang et al. 2021, "Synthesis of paracrystalline diamond", Nature, vol. 599, pp. 605–610, doi:10.1038/s41586-021-04122-w
  • Taniguchi M, Suga S, Seki M, Sakamoto H, Kanzaki H, Akahama Y, Endo S, Terada S & Narita S 1984, "Core-exciton induced resonant photoemission in the covalent semiconductor black phosphorus", Solid State Communications, vo1. 49, no. 9, pp. 867–7, doi:10.1016/0038-1098(84)90441-1
  • Taylor MD 1960, First Principles of Chemistry, Van Nostrand, Princeton
  • The Chemical News and Journal of Physical Science 1864, "Notices of books: Manual of the Metalloids", vol. 9, p. 22
  • The Chemical News and Journal of Physical Science 1897, "Notices of books: A Manual of Chemistry, Theoretical and Practical", by WA Tilden", vol. 75, pp. 188–189
  • Thornton BF & Burdette SC 2010, "Finding eka-iodine: Discovery priority in modern times", Bulletin for the History of Chemistry, vol. 35, no. 2, accessed September 14, 2021
  • Tidy CM 1887, Handbook of Modern Chemistry, 2nd ed., Smith, Elder & Co., London
  • Timberlake KC 1996, Chemistry: An Introduction to General, Organic, and Biological Chemistry, 6th ed., HarperCollinsCollege, ISBN 978-0-673-99054-9
  • Toon R 2011, "The discovery of fluorine", Education in Chemistry, Royal Society of Chemistry, accessed 7 October 2023
  • Tregarthen L 2003, Preliminary Chemistry, Macmillan Education: Melbourne, ISBN 978-0-7329-9011-4
  • Tyler PM 1948, From the Ground Up: Facts and Figures of the Mineral Industries of the United States, McGraw-Hill, New York
  • Vassilakis AA, Kalemos A & Mavridis A 2014, "Accurate first principles calculations on chlorine fluoride ClF and its ions ClF±", Theoretical Chemistry Accounts, vol. 133, no. 1436, doi:10.1007/s00214-013-1436-7
  • Vernon R 2013, "Which elements are metalloids?", Journal of Chemical Education, vol. 90, no. 12, pp. 1703‒1707, doi:10.1021/ed3008457
  • Vernon R 2020, "Organising the metals and nonmetals", Foundations of Chemistry, vol. 22, pp. 217‒233doi:10.1007/s10698-020-09356-6 (open access)
  • Vij et al. 2001, Polynitrogen chemistry. Synthesis, characterization, and crystal structure of surprisingly stable fluoroantimonate salts of N5+. Journal of the American Chemical Society, vol. 123, no. 26, pp. 6308−6313, doi:10.1021/ja010141g
  • Wächtershäuser G 2014, "From chemical invariance to genetic variability", in Weigand W and Schollhammer P (eds.), Bioinspired Catalysis: Metal Sulfur Complexes, Wiley-VCH, Weinheim, doi:10.1002/9783527664160.ch1
  • Wakeman TH 1899, "Free thought—Past, present and future", Free Thought Magazine, vol. 17
  • Wang HS, Lineweaver CH & Ireland TR 2018, The elemental abundances (with uncertainties) of the most Earth-like planet, Icarus, vol. 299, pp. 460–474, doi:10.1016/j.icarus.2017.08.024
  • Wasewar KL 2021, "Intensifying approaches for removal of selenium", in Devi et al. (eds.), Selenium contamination in water, John Wiley & Sons, Hoboken, pp. 319–355, ISBN 978-1-119-69354-3
  • Weeks ME & Leicester HM 1968, Discovery of the Elements, 7th ed., Journal of Chemical Education, Easton, Pennsylvania
  • Weetman C & Inoue S 2018, The road travelled: After main-group elements as transition metals, ChemCatChem, vol. 10, no. 19, pp. 4213–4228, doi:10.1002/cctc.201800963
  • Welcher SH 2009, High marks: Regents Chemistry Made Easy, 2nd ed., High Marks Made Easy, New York, ISBN 978-0-9714662-0-3
  • Weller et al. 2018, Inorganic Chemistry, 7th ed., Oxford University Press, Oxford, ISBN 978-0-19-252295-5
  • Wells AF 1984, Structural Inorganic Chemistry, 5th ed., Clarendon Press, Oxford, ISBN 978-0-19-855370-0
  • White JH 1962, Inorganic Chemistry: Advanced and Scholarship Levels, University of London Press, London
  • Whiteford GH & and Coffin RG 1939, Essentials of College Chemistry, 2nd ed., Mosby Co., St Louis
  • Whitten KW & Davis RE 1996, General Chemistry, 5th ed., Saunders College Publishing, Philadelphia, ISBN 978-0-03-006188-2
  • Wibaut P 1951, Organic Chemistry, Elsevier Publishing Company, New York
  • Wiberg N 2001, Inorganic Chemistry, Academic Press, San Diego, ISBN 978-0-12-352651-9
  • Williams RPJ 2007, "Life, the environment and our ecosystem", Journal of Inorganic Biochemistry, vol. 101, nos. 11–12, doi:10.1016/j.jinorgbio.2007.07.006
  • Windmeier C & Barron RF 2013, "Cryogenic technology", in Ullmann's Encyclopedia of Industrial Chemistry, doi:10.1002/14356007.b03_20.pub2
  • Winstel G 2000, "Electroluminescent materials and devices", in Ullmann's Encyclopedia of Industrial Chemistry, doi:10.1002/14356007.a09_255
  • Wismer RK 1997, Student Study Guide, General Chemistry: Principles and Modern Applications, 7th ed., Prentice Hall, Upper Saddle River, ISBN 978-0-13-281990-9
  • Woodward et al. 1999, "The electronic structure of metal oxides", In Fierro JLG (ed.), Metal Oxides: Chemistry and Applications, CRC Press, Boca Raton, ISBN 1-4200-2812-X
  • World Economic Forum 2021, Visualizing the abundance of elements in the Earth's crust, accessed 21 March 2024
  • Wulfsberg G 2000, Inorganic Chemistry, University Science Books, Sausalito, California, ISBN 978-1-891389-01-6
  • Yamaguchi M & Shirai Y 1996, "Defect structures", in Stoloff NS & Sikka VK (eds.), Physical Metallurgy and Processing of Intermetallic Compounds, Chapman & Hall, New York, ISBN 978-1-4613-1215-4
  • Yang J 2004, "Theory of thermal conductivity", in Tritt TM (ed.), Thermal Conductivity: Theory, Properties, and Applications, Kluwer Academic/Plenum Publishers, New York, pp. 1–20, ISBN 978-0-306-48327-1
  • Yin et al. 2018, Hydrogen-assisted post-growth substitution of tellurium into molybdenum disulfide monolayers with tunable compositions, Nanotechnology, vol. 29, no 14, doi:10.1088/1361-6528/aaabe8
  • Yoder CH, Suydam FH & Snavely FA 1975, Chemistry, 2nd ed, Harcourt Brace Jovanovich, New York, ISBN 978-0-15-506470-6
  • Young JA 2006, "Iodine", Journal of Chemical Education, vol. 83, no. 9, doi:10.1021/ed083p1285
  • Young et al. 2018, General Chemistry: Atoms First, Cengage Learning: Boston, ISBN 978-1-337-61229-6
  • Zhao J, Tu Z & Chan SH 2021, "Carbon corrosion mechanism and mitigation strategies in a proton exchange membrane fuel cell (PEMFC): A review", Journal of Power Sources, vol. 488, #229434, doi:10.1016/j.jpowsour.2020.229434
  • Zhigal'skii GP & Jones BK 2003, The Physical Properties of Thin Metal Films, Taylor & Francis, London, ISBN 978-0-415-28390-8
  • Zhu W 2020, Chemical Elements In Life, World Scientific, Singapore, ISBN 978-981-121-032-7
  • Zhu et al. 2014, "Reactions of xenon with iron and nickel are predicted in the Earth's inner core", Nature Chemistry, vol. 6, doi:10.1038/nchem.1925, PMID 24950336
  • Zhu et al. 2022, Introduction: basic concept of boron and its physical and chemical properties, in Fundamentals and Applications of Boron Chemistry, vol. 2, Zhu Y (ed.), Elsevier, Amsterdam, ISBN 978-0-12-822127-3
  • Zumdahl SS & DeCoste DJ 2010, Introductory Chemistry: A Foundation, 7th ed., Cengage Learning, Mason, Ohio, ISBN 978-1-111-29601-8