Question

If hydrogenis a combustible gas, then why it does not support combustion.

Answer 1

Combustible substances burn in oxygen and this process involves oxidation of the substance and formation of compound of the substance with oxygen (oxides). Oxygen is a supporter of combustion. Combustion of hydrogen forms water, a compound of hydrogen and oxygen. Sulfur burns to give SO₂ and SO₃, phosphorus burns to give P₂O₅ and organic compounds burn to form CO₂. Hydrogen is not electronegative enough to act as a strong oxidizing agent and hence does not support combustion.