Question

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Ozone is the most abundant element in the earth's crust and it makes up 1/5th of the atmosphere.
Oxygen made an appearance when the first single-celled lifeform evolved. Oxygen exists in two different
forms in the atmosphere-one is used by the living organisms for respiration, and the other one protects
us from harmful UV rays. When one of the form of oxygen is passed through an electric discharge or
in the presence of UV light, it converts to other form of oxygen.
(1) In which of the following form does oxygen exist in the atmospshere?
(b) 02
(c) 0₂
(d) both (b) and (c)
(ii) Which form of oxygen changes in presence of UV light and to what form?
(a) O₂, O₃
(b) 03, 02
(c) 03.0
(d) 02,
(ii) Depletion of ozone is mainly due to:
(a) Hydrocarbons
(b) Chlorofluorocarbon
(c) Nitrogenous compounds
(d) None of these
(iv) Which form of oxygen protects us from UV rays of sun?
(a) O2
(b) O
(c) 03
(d) both (a) and (c)
(v) The percentage of oxygen in the atmosphere is:
(c) 0.01%
(d) 0.1%
(a) 78%
(6) 21%​

Answer 1

Explanation:

First ka answer hai o2 niche

Second ka answer hai o2 o3 niche

Third ka answer hai chlorofluorocarbon

Fourth ka answer hai o2 niche

Fifth ka answer hai 78%