Hydrogen — Question 3

(a) Hydrogen burns quietly in oxygen with a pale blue flame and water is formed.

2H₂ + O₂ ⟶ 2H₂O

(b) Three volumes of hydrogen, reacts with one volume of nitrogen to form ammonia which is a basic gas.

$\text{N}_2 + 3\text{H}_2 \xrightleftharpoons[\text{450-500 \degree C}]{\text{Fe}} \text{2NH}_3 + \Delta$

(c) Hydrogen reduces oxides of less active metals e.g. zinc to form the reduced metal & water.

ZnO + H₂ ⟶ Zn + H₂O