(i) Explain about green chemistry in day-to-day life.
(ii) How acetaldehyde is commercially prepared by green chemistry?

Explanation

(i) 1. Dry cleaning of clothes: Solvents like tetrachloroethylene used in dry cleaning of clothes, pollute the ground water and are carcinogenic. In place of tetrachloro ethylene, liquefied CO, with suitable detergent is an alternate solvent used. Liquefied Co, is not harmful to the ground water. Nowadays `H_(2)O_(2)` is used for bleaching clothes in laundry, gives better result and utilises less water.
2. Bleaching of paper: Conventional method of bleaching was done with chlorine. Nowadays `H_(2)O_(2)` can be used for bleaching paper in the presence of catalyst.
3. Instead of petrol, methanol is used as a fuel in automobiles.
4. Neem based pesticides have been synthesised, which are more safer than the chlorinated hydrocarbons.
(ii) Acetaldehyde is commercially prepared by one step oxidation of ethene in the presence of ionic catalyst in aqueous medium with 90% yield.
`underset("Ethylane")(CH_(2)=CH_(2))overset("Catalyst")underset("Pd(II)/Cu(II)")tounderset("Acetaldehyde")(CH_(3)CHO)`