A complex salt is :

1. Zinc sulphate
2. Sodium hydrogen sulphate
3. Iron [ammonium sulphate]
4. Tetraammine copper [II] sulphate

Which one of the following will not produce acid with water ?

1. CO
2. CO₂
3. NO₂
4. SO₃

Lead sulphate can be prepared by the following methods.

P Reacting lead with sulphuric acid.
Q Reacting lead nitrate with sodium sulphate solution.
R Reacting lead oxide with sodium sulphate solution.

(a) Only P
(b) Only Q
(c) Only R
(d) Both Q and R

Assertion (A): All acids form hydronium ions when dissolved in water.

Reason (R): Every acid has hydrogen as the necessary element.

(a) Both A and R are true and R is the correct explanation of A

(b) Both A and R are true but R is not the correct explanation of A

(c) A is true but R is false

(d) A is false but R is true