Chemistry NCERT Exemplar Solutions Class 11th Chapter Fourteen

This is a Long Answers Type Questions as classified in NCERT Exemplar

(i) Many techniques are used to control or reduce the formation of photochemical smog. 

(1) If we control the primary precursors of photochemical smog, such as nitrogen dioxide and hydrocarbons, the secondary precursors such as ozone and PAN of the photochemical smog will automatically get reduced.

(2) Mostly catalytic converters are used in automobiles to prevent the release of nitrogen oxide and hydrocarbons to the atmosphere. 

(3) Certain plants e.g., Pinus, Juniparus, Quercus, Pyrus and Vitis metabolise nitrogen oxide and hence their plantation could help in this.

(ii) The organic solvents like- benzene, carbon tetrachloride, toluene etc., are highly toxic in nature. Everyone needs to be careful while using them. For bleaching the cloth hydrogen peroxide is used which is not harmful. Earlier chlorine was used for bleaching the clothes.

(iii) The synthetic detergents are found to be non-biodegradable and hence their use in daily life is to be avoided. Good quality soaps need to be prepared from vegetable oil as they are biodegradable in nature.

(iv) In place of petrol and diesel, the use of CNG and LPG should be preferred as they are pollution free fuels. The other sources such as hydrogen, ethanol etc. can also be used in place of petrol and diesel.