Question

Rajesh bought a bottle that was labelled as distilled water. He suspected it to be tap water. Draw and explain what test he could use to find out for sure?

Answer 1

Diagram:

Rajesh completed the circuit as shown in the diagram and watched the electrodes carefully. He noticed bubbles collecting at the electrodes, which indicated the formation of gases. Tap water contains several dissolved salts that allow electricity to flow through it, and in this process, tap water break downs into hydrogen and oxygen gases. Distilled water does not contain any dissolved salts, so it is a poor conductor of electricity. Therefore, no gases are formed at electrodes placed in it.
From this test, Rajesh confirmed that the water in the bottle was tap water and not distilled water.