Which of following is harmful to the ozone layer by decomposing o3 to o2? carbon dioxide sulfur dioxide greenhouse gases chlorofluorocarbons

We have to get the compound which is harmful to ozone layer by decomposing O₃ to O₂.

Chlorofluorocarbon (CFC) is responsible for ozone layer decomposition.

When chlorofluorocarbon (CFC) is released in atmosphere, they mix with normal atmospheric gas and reaches to stratosphere. In stratosphere, they get broken down by powerful UV radiations, releasing chlorine free radical.

CF₂Cl₂ (g) → Cl· (g) + CF₂Cl· (g)

The chlorine radical then reacts with stratospheric ozone to form chlorine monoxide  radical and molecular oxygen.

Cl· (g) + O₃ (g) → ClO· (g) + O₂ (g)

Reaction of chlorine monoxide radical with atomic oxygen produces more chlorine radicals.

ClO· (g) + O (g) → Cl· (g) + O₂ (g)

The chlorine radicals are continuously produced and cause depletion of ozone. This damages ozone layer.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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