Hydrogen

A colourless, odourless and tasteless gaseous element with the chemical symbol H.

Hydrogen is the lightest known substance, being fourteen and a half times lighter than air (hence its use in filling balloons), and over eleven thousand times lighter than water. It is very abundant, being an ingredient of water and of many other substances, especially those of animal or vegetable origin. It is highly inflammable.

Used as a secondary plasma gas in the plasma spraying process. Used as a fuel gas in combustion thermal spray processes.

Discovered in 1766 by Henry Cavendish and named after the Greek words hydro and genes meaning water and generator. In its natural form it has two atoms combined: H2.