Question

When we send electricity to pass through electrolysis jar we see gas bubble around both electrodes. Water electrolysis produces 30cm3 at cathode. a. What gas does it appear at each electrode? b. What would you do to identify the gas in the test tubes at each electrode? c. Calculate the volume of gas which appears at anode.

Answer 1

a) anode - hydrogen gas

cathode - oxygen gas

b) hydrogen gas - The gas burns with a pop sound

Oxygen gas - The gas rekindles a glowing splint

c) The volume of gas produced at the anode is 60cm3

Step-by-step explanation:

The electrolysis of water produces two volumes of hydrogen at the anode and one volume of oxygen at the cathode.

The hydrogen gas burns with a pop sound. It is easily identified by this test. Also, oxygen is known to rekindle a glowing splint and this is a commonly used test for oxygen gas.

Since the ratio of hydrogen produced at the anode to oxygen produced at the cathode is 2:1 by volume; then when 30cm3 of oxygen is produced at the cathode, 60cm3 of hydrogen is produced at the anode.