'A radical takes part — unsplit in a chemical reaction and retains its identity in reactions'. With reference to the radical:

(a) ammonium

(b) bisulphate

(c) carbonate — state the group of atoms present in each radical.

Differentiate between the following with suitable examples — A basic radical and a acid radical.

Explain the term – 'valency'. State giving reasons the valency of –

(a) chlorine in hydrogen chloride

(b) sulphate in sulphuric acid

(c) nitrogen in ammonia

(d) magnesium in magnesium oxide

Give the symbol and valency of the following elements and radicals.

(a) Potassium

(b) Sodium

(c) Hydrogen

(d) Calcium

(e) Aluminum

(f) Magnesium

(g) Zinc

(h) Chlorine [chloride]

(i) Sulphur [sulphide]

(j) Nitrogen [nitride]

(k) Oxygen [oxide]

(l) Ammonium

(m) Bicarbonate

(n) Nitrate

(o) Bisulphate

(p) Bisulphite

(q) Hydroxide

(r) Carbonate

(s) Sulphate

(t) Sulphite