Out of zinc and tin, which one protects iron better even after cracks and why ?

Iron nails become reddish brown in colour and solution becomes green in colour.

(c) Food cans are coated with tin and not with zinc because zinc is more reactive than tin.

Hint- Epidermis having thick cuticle and waxy substances to prevent the invasion of parasites.

(c) Zinc is more reactive than tin.

Among iron and mercury, iron is a better conductor of electricity because the resistivity of iron (10.0 x 10-8 Ω m) is less than that of mercury (94.0 x 10-8 Ωm).

A fuse is usually made of tin or tin-copper alloy because it has Iow melting point.

Advantages: (i) Provides the resources for the present generation. (ii) Preserves the resources for the future generation as well Reuse is better than recycling because it does not involve use of energy.

(a) North pole is almost equal to the south pole.

(i)—(c), (ii)—(a), (iii)—(b), (iv)—(b), (v)—(b).

The correct answer is (c) Ozone.