Question

Which of the following observations is true when the switch is closed in the given circuit?

• A. Current is passed from zinc rod to copper rod.
• B. Electrical energy is converted into chemical energy .
• C. Copper electrodes begin to dissolve in the sulphuric acid.
• D. Bubbles are formed on the copper rod.

Answer 1

The correct option is D Bubbles are formed on the copper rod.

When the switch is closed, the given circuit will act like a cell. The LED will start glowing. In this cell, chemical energy is converted into electrical energy.
Here, copper rod and zinc rod are used as electrodes and dilute sulphuric acid is used as an electrolyte.
When zinc and copper rods are immersed into dilute sulphuric acid, zinc slowly begins to dissolve in the sulphuric acid. Bubbles are formed on the copper rod. Current is passed from copper rod to zinc rod.