Green chemistry in day-to-day life is in the use of:

Step-by-step solution

Chlorine gas was used earlier for bleaching paper. These days, hydrogen peroxide H 2 O 2 is used with suitable catalyst. Tetrachloroethene Cl 2 C = CCl 2 was earlier used as solvent for dry cleaning. The compound contaminates the ground water and is also a suspected carcinogen. Replacement of halogenated solvent by liquid CO 2 will result in less harm to groundwater. Hence, given statement ( 4 ) is correct.