Chemistry GREEN CHEMISTRY

### Topics to be covered

=> Green chemistry
=> Green chemistry in day- to-day life

### GREEN CHEMISTRY

color{green}(" ★ 𝐈𝐧𝐭𝐫𝐨𝐝𝐮𝐜𝐭𝐢𝐨𝐧")

★ In the last few years overexploitation of soil and excessive use of fertilizers and pesticides have resulted in the deterioration of soil, water and air.Therefore there lies a need to discover methods reduction of deterioration of the environment.

★ Green chemistry is a production process that would bring about minimum pollution or deterioration to the environment. The byproducts generated during a process, if not used gainfully, add to the environmental pollution. The waste generation and its disposal both are economically unsound. color{green}("𝐔𝐭𝐢𝐥𝐢𝐬𝐚𝐭𝐢𝐨𝐧 𝐨𝐟 𝐞𝐱𝐢𝐬𝐭𝐢𝐧𝐠 𝐤𝐧𝐨𝐰𝐥𝐞𝐝𝐠𝐞 𝐛𝐚𝐬𝐞 𝐟𝐨𝐫 𝐫𝐞𝐝𝐮𝐜𝐢𝐧𝐠 𝐭𝐡𝐞 𝐜𝐡𝐞𝐦𝐢𝐜𝐚𝐥") color{green}("𝐡𝐚𝐳𝐚𝐫𝐝𝐬 𝐚𝐥𝐨𝐧𝐠 𝐰𝐢𝐭𝐡 𝐭𝐡𝐞 𝐝𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭𝐚𝐥 𝐚𝐜𝐭𝐢𝐯𝐢𝐭𝐢𝐞𝐬") color{green}("𝐢𝐬 𝐭𝐡𝐞 𝐟𝐨𝐮𝐧𝐝𝐚𝐭𝐢𝐨𝐧 𝐨𝐟 𝐠𝐫𝐞𝐞𝐧 𝐜𝐡𝐞𝐦𝐢𝐬𝐭𝐫𝐲")

color{green}(" ★ 𝐏𝐎𝐈𝐍𝐓𝐒 𝐓𝐎 𝐁𝐄 𝐊𝐄𝐏𝐓 𝐈𝐍 𝐌𝐈𝐍𝐃 𝐖𝐇𝐈𝐋𝐄 𝐏𝐄𝐑𝐅𝐎𝐑𝐌𝐈𝐍𝐆 𝐀𝐍𝐘 𝐑𝐄𝐀𝐂𝐓𝐈𝐎𝐍")

★ Benzene, toluene, carbon tetrachloride etc., being highly toxic should be used carefully.

★ Extent of any reaction depends upon physical parameters like temperature, pressure and use of catalyst.

★ In a chemical reaction, if reactants are fully converted into useful environmental friendly products by using an environment friendly medium then there would be no chemical pollutants introduced in the environment.

★ During a synthesis, starting materials must be chosen such that they can be converted into end products with yield approximately upto 100 per cent. This can be achieved by arriving at optimum conditions of synthesis.

★ Water is cost effective, noninflammable and devoid of any carcinogenic effects and has high specific heat and low volatility. So synthetic reactions must be carried out in aqueous medium .

### Green Chemistry in day-to-day Life

color{green}("(𝐢) 𝐃𝐫𝐲 𝐂𝐥𝐞𝐚𝐧𝐢𝐧𝐠 𝐨𝐟 𝐂𝐥𝐨𝐭𝐡𝐞𝐬:")

Tetra chlroroethene color{red}((Cl_2C=C Cl_2)) earlier used as solvent for dry cleaning has been repaced because it contaminates the ground water and is also a suspected carcinogen.Now liquefied carbondioxide, with a suitable detergent is used. Replacement of halogenated solvent by liquid color{red}(CO_2) will result in less harm to ground water. Hydrogen peroxide color{red}((H_2O_2)) is also used for the purpose of bleaching clothes in the process of laundary, which gives better results and makes use of lesser amount of water.

color{green}("(𝐢𝐢) 𝐁𝐥𝐞𝐚𝐜𝐡𝐢𝐧𝐠 𝐨𝐟 𝐏𝐚𝐩𝐞𝐫:")

Earlier chlorine gas was used for bleaching paper but now hydrogen peroxide color{red}((H_2O_2)) with suitable catalyst is used.

color{green}("(𝐢𝐢𝐢) 𝐒𝐲𝐧𝐭𝐡𝐞𝐬𝐢𝐬 𝐨𝐟 𝐂𝐡𝐞𝐦𝐢𝐜𝐚𝐥𝐬:")

Ethanal color{red}((CH_3CHO)) is now commercially prepared by one step oxidation of ethene in the presence of ionic catalyst in aqueous medium with a yield of 90%.

color{red}(CH_2 = CH_2 + O_2 underset(" Pd(II) / Cu (II) (in water)") overset("catalyst")→ CH_3CHO ( 90%))

color{green}("Green chemistry, in a nutshell, is a cost effective approach which") color{green}(" involves reduction in material, energy consumption and waste generation.")