Prepare- a fresh solution of sodium hydroxide in a test tube by dissolving 3-4 pellets of it in 5 mL, of water. Drop a piece of aluminium foil into it. Bring a burnish matchstick near the mouth of the test tube. Observe carefully. What does the 'pop' sound indicate?

Prepare- a fresh solution of sodium hydroxide in a test tube by dissol

1.	Prepare- a fresh solution of sodium hydroxide in a test tube by dissolving 3-4 pellets of it in 5 mL, of water. Drop a piece of aluminium foil into it. Bring a burnish matchstick near the mouth of the test tube. Observe carefully. What does the 'pop' sound indicate?
Answer» ANSWER :We will observe that metal reacts with sodium HYDROXIDE producing HYDROGEN GAS with a 'pop' sound. The 'pop' sound indicates that hydrogen gas is PRESENT.