Give reasons:

Impure diamond is used to cut glass.

Give reasons:

Gold is mixed with copper and nickel.

Name the metals present in the following alloys:

(a) Brass

(b) Bronze

(c) Duralumin

(d) Stainless steel

Give four differences between metals and non-metals with reference to their:

(a) Melting point and boiling point

(b) Conductivity of heat and electricity

(c) Malleability

(d) Solubility in water.