Question

List at least two pros and cons of using road salt in the winter

Answer 1

PROS: It dissolves in water and lowers the freezing point of water so a lower temperature is required for ice to form. This makes the road less treacherous for vehicles. Road salt is usually cheap and readily available. Since salt is already a constituent of sea water, it does not cause pollution when washed away.
CONS: Salt dissolved in water is corrosive to metal. A metalled road surface may eventually be attacked by the corrosive, leading to damage of the surface. The salt solution is splashed on to the bodies and into the engine parts of vehicles and, unless properly protected, the metal parts of the vehicle will become corroded. Salt solution is a good conductor of electricity so it could under certain circumstances affect the electrical circuits within vehicles. When the salt solution dries out it leaves a deposit of white salt on the surface. The spreading of road salt is often carried out by specially equipped vehicles, so there is a cost incurred in salt spreading. Usually salt is mixed with grit.

Answer 2

The advantages of the use of road salt in winter are-

(a) Road salts can melt the ice during the winter that helps in the reduction of accidents.

(b) It increases the frictional force.

(c) It is less costly and easily available.

The disadvantages of the use of road salt is-

(a) Certain parts of the cars get rusted due to the increasing iron oxide formation. This iron oxide is formed when the free-floating ions react with the water.

(b) It causes damage and corrodes traffic infrastructures.

(c) The addition of rock salts can lead to the destruction of various types of plants as it does not allow the plants to take in water.

(d) The water gets contaminated as it mixes with the salt, as a result of which the aquatic lives are affected.