Give a balanced equation for the reaction: Dilute nitric acid and copper carbonate.

Identify the gas evolved when:

(i) Sulphur is treated with concentrated nitric acid.

(ii) A few crystals of KNO₃ are heated in a hard glass test tube.

Give a balanced equations for: Oxidation of carbon with concentrated nitric acid.

Fill in the blank from the choices given in the bracket:

Cold, dil. nitric acid reacts with copper to form …………… [Hydrogen, nitrogen dioxide, nitric oxide].