Complete and balance the following equations:

(a) NH₄Cl + Ca(OH)₂ ⟶

(b) CuSO₄ + NH₄OH ⟶

(c) Cu + Conc. HNO₃ ⟶

State a relevant reason for the following:

(a) Hydrogen chloride gas cannot be dried over quick lime.

(b) Ammonia gas is not collected over water.

Solve the following numerical problem.

Ethane burns in oxygen according to the chemical equation:

2C₂H₆ + 7O₂ ⟶ 4CO₂ + 6H₂O

If 80 ml of ethane is burnt in 300 ml of oxygen, find the composition of the resultant gaseous mixture when measured at room temperature.

The following questions are pertaining to the laboratory preparation of Ammonia gas from Magnesium nitride:

(a) Write a balanced chemical equation for its preparation.

(b) Why is this method seldom used?

(c) How do you identify the gas formed?