It is difficult to use hydrogen as a source of energy, although its calorific value is quite high. Explain.

(i) When hydrogen gas is lighted, it burns with an explosion which is very unsafe.
(ii) It is very expensive to produce hydrogen gas by the electrolysis of water because it requires a lot of electricity.
(iii) It is very difficult to store and transport hydrogen gas as it is explosively inflammable.
Hence it is difficult to use hydrogen as a source of energy, though it has high calorific value.