The term green chemistry may be defined as the program of developing new chemical products and chemical processes or making improvement in the already existing compounds and processes so as to make them less harmful to human health and environment.
For attaining success in objectives of green chemistry, following particles are to be used

(i) The use of starting materials, reagents and solvents which are less hazardous to man and his environment.
(ii) More efficient use of raw materials.
(iii) Utilisation of chemical reactions which completely incorporate the starting materials into the final products.
(iv) Search for new alternatives which are environmental friendly.

Collective efforts in the field of green chemistry have made tremendous impact on several industrial sectors in recent years. Some of the achievements in this field are as follows:

(i) Development of dense phase, carbon dioxide: Dense phase has been recently developed chemical product with amazing characteristics. It has ability to clean everything. It can be used as recyclable solvent and finds number of applications in food industry.
(ii) Development of fuel cells for cellular phones which can last for the full life time of the phone.
(iii) Development of process involving use of as a blowing agent for manufacture of poly styrene foam. This technology eliminates the use of chloro fluoro carbon as blowing agent.
(iv) Development of safer marine antifouling compound sea-nine that dexamplerades more rapidly than organotins which persists in marine environment and cause pollution Prob.s.

Thus Green Chemistry programs recognise and promote fundamental break through in chemistry that accomplish prevention in a cost effective manners.

Illustration 1. Name some factors which cause soil pollution.

Solution: (i) Indiscriminate use of fertilizers
(ii) Indiscriminate use of pesticides
(iii) Dumping of large quantities of waste materials
(iv) Deforestation

« Click Here for Previous Topic Click Here for Next Topic »

Class 12 Enviromental Chemistry All Topic Notes Class 12 Chemistry All Chapters Notes