Chemical reactions of the elements
Reaction of hydrogen with air
Hydrogen is a colourless gas, H2, that is lighter than air. Mixtures of hydrogen gas and air do not react unless ignited with a flame or spark, in which case the result is a fire or explosion with a characteristic reddish flame whose only products are water, H2O.
2H2(g) + O2(g) → 2H2O(l)
Reaction of hydrogen with water
Hydrogen does not react with water. It does, however, dissolve to the extent of about 0.00160 g kg-1 at 20°C (297 K) and 1 atmosphere pressure.
Reaction of hydrogen with the halogens
Hydrogen gas, H2, reacts with fluorine, F2, in the dark to form hydrogen(I) fluoride.
H2(g) + F2(g) → 2HF(g)
Reaction of hydrogen with acids
Hydrogen does not react with dilute acids.
Reaction of hydrogen with bases
Hydrogen does not react with dilute bases.