question_answer 39)

  Electrolysis of water is a decomposition reaction. The mole ratio of hydrogen and oxygen gases liberated during electrolysis of water is (a) 1 : 1                                 (b) 2 : 1                                 (c) 4 : 1                                  (d) 1 : 2

Answer:

  (b) The water decomposes during electrolysis to form hydrogen and oxygen gases in the ratio 2 : 1 by volume.