The atomic ratio is a measure of the ratio of atoms of one kind (i) to another kind (j). A closely related concept is the atomic percent (or at.%), which...

The atomic mass (ma or m) is the mass of an atom. Although the SI unit of mass is the kilogram (symbol: kg), atomic mass is often expressed in the non-SI...

quantity defined as the ratio of the average mass of atoms of a chemical element in a given sample to the atomic mass constant. The atomic mass constant (symbol:...

The Redfield ratio or Redfield stoichiometry is the consistent atomic ratio of carbon, nitrogen and phosphorus found in marine phytoplankton and throughout...

The neutron–proton ratio (N/Z ratio or nuclear ratio) of an atomic nucleus is the ratio of its number of neutrons to its number of protons. Among stable...

of two hydrogen atoms bonded to a single oxygen atom (i.e. H2O). The atomic ratio of hydrogen to oxygen is always 2:1 in every molecule of water. Pure...

The atomic number or nuclear charge number (symbol Z) of a chemical element is the charge number of an atomic nucleus. For ordinary nuclei composed of...

The diagram cross-plots the hydrogen:carbon atomic ratio as a function of the oxygen:carbon atomic ratio. Beginning around 2003, the diagrams are often...

terms of conventional oil retorting. Hydrogen:carbon atomic ratio > 1.25 Oxygen:carbon atomic ratio < 0.15 Derived principally from lacustrine algae, deposited...

freeze temperature (solidus) "meet at the pure element endpoints of the atomic ratio axis while slightly separating in the mixture region of this axis". In...

strongest surface gravity of any moon, and the lowest amount of water by atomic ratio of any known astronomical object in the Solar System. It was discovered...

On 6 and 9 August 1945, the United States detonated two atomic bombs over the Japanese cities of Hiroshima and Nagasaki, respectively. The bombings killed...

An atomic clock is a clock that measures time by monitoring the resonant frequency of atoms. It is based on atoms having different energy levels. Electron...

Atomic theory is the scientific theory that matter is composed of particles called atoms. The definition of the word "atom" has changed over the years...

confused with the standard atomic weight (also called atomic weight) of an element, which is the ratio of the average atomic mass of the different isotopes...

lowest mass) has an atomic weight of 1.007825 Da. The value of this number is called the atomic mass. A given atom has an atomic mass approximately equal...

{C}}^{6+})}}=0.000\,274\,365\,185\,89(58)} As the relative atomic mass of 12C6+ ions is very nearly 12, the ratio of frequencies can be used to calculate a first...

surface, followed by indium plating, with layer thickness matching the 1:2 atomic ratio. A heat treatment then causes interdiffusion of the metals and formation...

copper ores. The reasons for this is its high copper content (66.7% atomic ratio and nearly 80% by weight) and the ease at which copper can be separated...

; Thomas, P. (2002). "Calcium phosphate apatites with variable Ca/P atomic ratio I. Synthesis, characterisation and thermal stability of powders". Biomaterials...

of two hydrogen atoms bonded to a single oxygen atom (i.e. H2O). The atomic ratio of hydrogen to oxygen is always 2:1 in every molecule of water. Pure...

for most elements. Even for the lightest elements, whose ratio of neutron number to atomic number varies the most between isotopes, it usually has only...

of a quantum system weakly coupled to its environment Redfield ratio, the atomic ratio of carbon, nitrogen and phosphorus found in phytoplankton and throughout...

isotope ratio cycles are cyclical variations in the ratio of the abundance of oxygen with an atomic mass of 18 to the abundance of oxygen with an atomic mass...

The dalton or unified atomic mass unit (symbols: Da or u) is a unit of mass defined as ⁠1/12⁠ of the mass of an unbound neutral atom of carbon-12 in its...

potassium ions and the irregular sites by smaller sodium ions, yielding an atomic ratio of sodium to potassium of 3:1. This corresponds to an ideal weight percentage...

Graphite oxide is a compound of carbon, oxygen, and hydrogen where there is a ratio between 2.1 and 2.9 of carbon to oxygen. Graphite oxide is typically a yellowish...

effect) Atomic mass: (applies to each element) the average mass of the atoms of an element, in daltons (Da), a.k.a. atomic mass units (amu). Atomic number:...

Atomic absorption spectroscopy (AAS) and atomic emission spectroscopy (AES) is a spectroanalytical procedure for the quantitative determination of chemical...

on the Earth. However, there are seasonal changes in the molecular-to-atomic ratio of the neutral atmosphere that cause the summer ion loss rate to be even...