Question

On passing the current in water voltameter, the hydrogen
A. Liberated at anode
B. Liberated at cathode
C. Doesn’t liberate
D. Remains in the solution

Answer 1

Hint: We need to understand a water voltameter's structure and working principle. Basic knowledge and understanding of the elementary composition of water (the electrolyte) are necessary.

Complete Step by Step Answer:
A water voltameter is a piece of equipment or apparatus used for measuring the quantity of electricity passed through a conductor by the amount of electrolysis produced. Electrolysis can be defined as the separation of different parts of the chemical composition of a liquid with the help of an electric current.
When electric current passes through the water voltameter, electrolysis takes place. This results in the breakdown of water into its elemental components, i.e., hydrogen and oxygen.
The hydrogen part contains positive charge, while the oxygen part contains negative charge. According to the principles of electrolysis, positive charges are liberated at the cathode and negative charges are liberated at the anode.

Hence, hydrogen will get liberated at cathode as it contains positive charge.
A better understanding could be gained from the diagram given below. It depicts the working of a water voltameter when an electric current is being passed through it.
The correct answer is option B.

Additional information: Water voltameter is also known as Hofmann voltameter in honour of August Wilhelm von Hofmann, its inventor.

Note: If pure water is used in the voltameter, electrolysis will not happen as pure water is a non-conductor of electricity. But if there is an ionic compound such as sodium chloride or sulphuric acid present in the solution, the process will get started automatically upon applying of electric current.