Hydrogen is the first element in the periodic table of elements therefore its period number is one. The atomic symbol for hydrogen is H and its atomic number is one.

Hydrogen has an atomic weight of 1.00794 (7)g, and is a colorless gas. It is easily the most abundant gas on Earth. Hydrogen can be seen most often in water because when two parts of hydrogen combine with one part of oxygen it creates water or (H2O). Hydrogen is the simplest element known to man with only one proton per each hydrogen atom.

It is rare for hydrogen to be found by itself. It is usually bonded with another element. When it can be isolated hydrogen is a colorless, odorless gas. Steam reforming of the natural gas methane is one of the most used processes to make hydrogen. This process accounts for most of the hydrogen made in the United States today.

Hydrogen is also extremely flammable. One of the biggest examples of the flammability of hydrogen is the Hindenburg explosion in which hydrogen was used instead of helium to fill a blimp that later caught fire and exploded.