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3. Group IIIA and Group IVA Elements eLearn.Punjab

Aluminium does not react with dilute sulphuric acid. However, it is oxidized
by hot concentrated sulphuric acid to liberate sulphur dioxide gas.

2Al(s) + 6H2SO4 (aq) → Al2 (SO4 )3 (aq) + 6H2O() + 3SO2 (g)

Aluminium does not react with nitric acid at any concentration,
probably because of the formation of protective layer of aluminium
oxide. The acid is said to render the aluminium passive. Nitric acid
is, therefore, frequently transported in aluminium containers.
Aluminium dissolves in both sodium and potassium hydroxides
to form a soluble aluminate, with the evolution of hydrogen.

2Al(s) + 2NaOH(aq) + 6H2O() → 2NaAl(OH)4 (aq) + 3H2 (g)

USES

1. Aluminium is very-light (nearly three times less dense than iron) but posseses
high tensile strength. These properties account for its extensive use in the
transport industries, in the construction of aircrafts, ships and cars.

2. It is an excellent conductor of both electricity and heat. Thus, it is used as
heat exchanger in chemical, oil and other industries. Heavy duty electrical
cables are made of aluminium metal.

3. Aluminium is an excellent reflector of radiant energy. For this reason, it is
commonly used to insulate buildings. Aluminium foil is also used to jam radar.

4. It is non-magnetic and is thus used in navigational equipment.
5. It is a good reducing agent and can thus be used for this purpose in the

chemical and steel industries.
6. It is non-toxic and can be used for making food and brewing equipments
and in packaging.
7. Aluminium readily forms alloys with other metals like copper, magnesium,
nickel and zinc.

8. At homes, aluminium is found in the form of cooking utensils, window frames
and kitchen foil.
9. Aluminium is used for making petrol and milk storage tanks because it
reflects heat and prevents them of being over heated in the sun.

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