Question

In the circuit below, the lamp lights up.

What could X be?

Options

• a solution of alcohol in water

• a solution of sodium chloride in water

• Sugar solution

• solid potassium chloride

Answer 1

A solution of sodium chloride in water

Explanation:

For the lamp to light up, substance X must be an electrolyte that contains free mobile ions to conduct electricity. A solution of sodium chloride splits into free-moving Na⁺ and Cl⁻ ions in water, which completes the circuit and allows current to flow.