Explain the following:

(a) Zinc is used to cover iron so as to prevent rusting of iron. Why?

(b) In construction work, why is the alloy of aluminium–duralumin used rather than pure aluminium?

What is an alloy? How do the properties of an alloy differ from it's constituents?

Name an alloy of:

(a) Aluminium used in aircraft construction.

(b) Lead used in electrical wiring or electrical work in joining metals.

(c) Copper in electrical appliances or household vessels.

(d) Zinc used in naval ships.

What is an amalgam? State it's use with an example.