You must have seen tarnished copper vessels being cleaned with lemon or tamarind juice. Explain why these sour substances are effective in cleaning the vessels.
Give reasons : Platinum, gold and silver are used to make jewellery.
In the electrolytic refining of a metal $M$, what would you take as the anode, the cathode and the electrolyte ?
State two ways to prevent the rusting of iron.
An element reacts with oxygen to give a compound with a high melting point. This compound is also soluble in water. The element is likely to be