Question

Give reasons-

a) Copper is used to make hot water tanks and not steel.

b) Gold and silver are used to make jewellery.

c) Sodium, potassium and lithium are stored under oil.​

Answer 1

Answer:

(a) Platinum, gold and silver are used to make jewellery because they are noble metals and thus dont react with air & moisture. (b) Sodium, potassium and lithium are stored under oil because they are highly reactive with air/water but unreactive with oil..

Answer 2

Answer:

a). If the hot water tanks are made of steel (an alloy of iron), then iron would react vigorously with the steam formed from hot water. That is why copper is used to make hot water tanks, and not steel.