Explain why:

(a) Cu, though a good conductor of electricity, is a non electrolyte.

(b) Solid sodium chloride does not allow electricity to pass through.

Choose A, B, C or D to match the descriptions (i) to (v) below. Some alphabets may be repeated.

A. non-electrolyte

B. strong electrolyte

C. weak electrolyte

D. metallic conductor

(i) Molten ionic compound

(ii) Carbon tetrachloride

(iii) An aluminium wire

(iv) A solution containing solvent molecules, solute molecules and ions formed by the dissociation of solute molecules.

(v) A sugar solution with sugar molecules and water molecules.

Name two substances in each case:

(a) Contain only molecule

(b) Contain only ions

(c) Contain ions as well as molecules

Select the ion in each case that would get selectively discharged from the aqueous mixture of the ions listed below:

(a) SO₄^2-, NO₃^-, and OH^-

(b) Pb²⁺, Ag⁺, and Cu²⁺