sometimes called dihydrogen, but more commonly called hydrogen gas, molecular hydrogen or simply hydrogen. It is colorless, odorless, non-toxic, and highly...

In chemistry, a hydrogen bond (or H-bond) is primarily an electrostatic force of attraction between a hydrogen (H) atom which is covalently bonded to a...

Hydrogen peroxide is a chemical compound with the formula H2O2. In its pure form, it is a very pale blue liquid that is slightly more viscous than water...

Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel...

Hydrogen gas is produced by several industrial methods. Nearly all of the world's current supply of hydrogen is created from fossil fuels.: 1  Most hydrogen...

Hydrogen sulfide is a chemical compound with the formula H2S. It is a colorless chalcogen-hydride gas, and is poisonous, corrosive, and flammable, with...

Hydrogen cyanide (formerly known as prussic acid) is a chemical compound with the formula HCN and structural formula H−C≡N. It is a highly toxic and flammable...

A hydrogen atom is an atom of the chemical element hydrogen. The electrically neutral hydrogen atom contains a nucleus of a single positively charged proton...

The compound hydrogen chloride has the chemical formula HCl and as such is a hydrogen halide. At room temperature, it is a colorless gas, which forms white...

Hydrogen embrittlement (HE), also known as hydrogen-assisted cracking or hydrogen-induced cracking (HIC), is a reduction in the ductility of a metal due...

A hydrogen vehicle is a vehicle that uses hydrogen to move. Hydrogen vehicles include some road vehicles, rail vehicles, space rockets, forklifts, ships...

Liquid hydrogen (H2(l)) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must...

as acidity or basicity, historically denotes "potential of hydrogen" (or "power of hydrogen"). It is a logarithmic scale used to specify the acidity or...

The hydrogen economy is an umbrella term for the roles hydrogen can play alongside low-carbon electricity to reduce emissions of greenhouse gases. The...

Hydrogen fluoride (fluorane) is an inorganic compound with chemical formula HF. It is a very poisonous, colorless gas or liquid that dissolves in water...

Hydrogen (1H) has three naturally occurring isotopes: 1H, 2H, and 3H. 1H and 2H are stable, while 3H has a half-life of 12.32(2) years. Heavier isotopes...

A hydrogen ion is created when a hydrogen atom loses an electron. A positively charged hydrogen ion (or proton) can readily combine with other particles...

Green hydrogen (GH2 or GH2) is hydrogen produced by the electrolysis of water, using renewable electricity. Production of green hydrogen causes significantly...

Hydrogenics is a developer and manufacturer of hydrogen generation and fuel cell products based on water electrolysis and proton-exchange membrane (PEM)...

Metallic hydrogen is a phase of hydrogen in which it behaves like an electrical conductor. This phase was predicted in 1935 on theoretical grounds by...

includes hydrogen trains, zero-emission multiple units, or ZEMUs — generic terms describing rail vehicles, large or small, which use on-board hydrogen fuel...

water into oxygen (O 2) and hydrogen (H 2) gas by electrolysis. Hydrogen gas released in this way can be used as hydrogen fuel, but must be kept apart...

Several methods exist for storing hydrogen. These include mechanical approaches such as using high pressures and low temperatures, or employing chemical...

Hydrogen safety covers the safe production, handling and use of hydrogen, particularly hydrogen gas fuel and liquid hydrogen. Hydrogen possesses the NFPA...

Natural hydrogen (known as white hydrogen, geologic hydrogen, geogenic hydrogen, or gold hydrogen), is hydrogen that is formed by natural processes (as...

Hydrogen-alpha, typically shortened to H-alpha or Hα, is a deep-red visible spectral line of the hydrogen atom with a wavelength of 656.28 nm in air and...

A hydrogen maser, also known as hydrogen frequency standard, is a specific type of maser that uses the intrinsic properties of the hydrogen atom to serve...

A hydrogen internal combustion engine vehicle (HICEV) is a type of hydrogen vehicle using an internal combustion engine. Hydrogen internal combustion...

Hydrogen iodide (HI) is a diatomic molecule and hydrogen halide. Aqueous solutions of HI are known as hydroiodic acid or hydriodic acid, a strong acid...

compound with the chemical formula CH4 (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent...