a.

Electrons flow towards the Zinc rod

b.

The Zinc rod dissolves

c.

The temperature of the soil changes

d.

The blue colour of the solution gradually disappears

a.

Hydrogen sulphide

b.

Carbon(IV)oxide

c.

Sulphur(IV)oxide

d.

Carbon(II)oxide

a.

112

b.

120

c.

56

d.

14

a.

Heating aluminium oxide with coke in a furnace

b.

The electrolysis of fused aluminium oxide in cryolite

c.

Treating cryolite with sodium hydroxide solution under pressure

d.

Heating sodium aluminium silicate to a high temperature