Hydrogen

Occurrence

Hydrogen is the most abundant element in the universe, making up 75% of normal matter by mass and over 90% by number of atoms. {{ref|education.jlab.org}} This element is found in great abundance in stars and gas giant planets. It is very rare in the Earth's atmosphere (1 ppm by volume), because being the lightest gas causes it to escape Earth's gravity, though when compounds are considered, it is the tenth most abundant element on Earth. The most common source for this element on Earth is water, which is composed two parts hydrogen to one part oxygen (H2O). Other sources include most forms of organic matter (currently all known life forms) including coal, natural gas, and other fossil fuels. Methane (CH4) is an increasingly important source of hydrogen.

Related Topics:
Abundant - Mass - Atom - Star - Earth - Ppm - Compounds - Water - Oxygen - Coal - Natural gas - Fossil fuel - Methane - C

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Throughout the Universe, hydrogen is mostly found in the plasma state whose properties are quite different to molecular hydrogen. As a plasma, hydrogen's electron and proton are not bound together, resulting in very high electrical conductivity, even when the gas is only partially ionised. The charged particles are highly influenced by magnetic and electric fields, for example, in the Solar Wind they interact with the Earth's magnetosphere giving rising to Birkeland currents and the aurora.

Related Topics:
Plasma - Solar Wind - Magnetosphere - Birkeland current - Aurora

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Hydrogen can be prepared in several different ways: steam on heated carbon, hydrocarbon decomposition with heat, reaction of a strong base in an aqueous solution with aluminium, water electrolysis, or displacement from acids with certain metals. Commercial bulk hydrogen is usually produced by the steam reforming of natural gas. At high temperatures (700–1100 °C), steam reacts with methane to yield carbon monoxide and hydrogen.

Related Topics:
Steam - Carbon - Hydrocarbon - Aqueous solution - Aluminium - Electrolysis - Acid - Metal - Steam reforming - Natural gas - Carbon monoxide

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

:CH4 + H2O ? CO + 3 H2

Related Topics:
CH₄ - H₂O - CO

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Additional hydrogen can be recovered from the carbon monoxide through the water-gas shift reaction:

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

:CO + H2O ? CO2 + H2

Related Topics:
CO - H₂O - CO₂

~ ~ ~ ~ ~ ~ ~ ~ ~ ~