Chemistry
State what are chlorofluorocarbons and give their use. Give a reason why they are ozone depleting. State a suitable alternative to chlorofluorocarbons which are non-ozone depleting.
Ammonia
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Answer
Chlorofluorocarbons (CFC’s) are compounds of carbon with chlorine or fluorine. CFC are chemicals which like liquefied ammonia gas are used in refrigeration gas.
They enter the atmosphere due to their use as coolants in refrigeration and A/C plants and aerosol sprays and cause ozone depletion in the atmosphere.
Chlorofluorocarbons (CFC’s) are decomposed by U.V. rays to give free Cl radicals.
CFCl3 ⟶ Cl atom
This Cl atom breaks the ozone layer causing ozone depletion.
Cl + O3 [ozone] ⟶ ClO + O2
Hence, ozone layer located in the stratosphere above the earth, which prevents harmful U.V. rays from reaching the earth, gets depleted.
Suitable alternatives to chlorofluorocarbons which are non-ozone depleting include Hydrochlorofluorocarbons [HCFC]
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Related Questions
Name an ammonium salt which is a constituent of
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(b) dry cells.
Give reasons for the use of the named ammonium salt for the same.
Give one use with reason of
(i) an aqueous solution of NH3
(ii) liquefied NH3.
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(b) The gaseous product obtained is further oxidized. - Ammonium nitrite undergoes thermal decomposition.
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