Hydrogen is a colorless, odorless gas, burning with a pale blue flame and very little light, but with great heat. It is chemically prepared by the action of zinc or iron, and hydrochloric or sulphuric acid. Zinc and sulphuric acid form zinc sulphate and hydrogen. The reactions may be represented by the equations:

Zn

+

H1SO4

=

ZnSO4

+

2H

Zinc

Sulphuric Acid

Zinc Sulphate

Hydrogen

Fe

+

H1SO4

=

FeSO4

+

2 H

Iron

Sulphuric Acid

Iron Sulphate

Hydrogen