Question

Two forms of oxygen found in the atmosphere are:
A. Water and oxygen
B. Oxygen and carbon dioxide
C. Carbon dioxide and water
D. Oxygen and ozone

Answer 1

Hint: Solve this question by looking into the daily environment. One of them is found in the stratosphere of the atmosphere and the other one is used by living organisms for respiration.

Complete step by step answer:
Oxygen –\[{{O}_{2}}\]
Atmospheric oxygen refers to the abundance of molecular oxygen -\[{{O}_{2}}\] in the atmosphere (around 20.95%). It is present majorly in the troposphere. It is very essential for all lives to flourish. The main source of atmospheric oxygen is photosynthesis, which produces free oxygen from carbon dioxide and water.
Ozone – \[{{O}_{3}}\]
Ozone, also known as trioxygen, is an inorganic molecule formed in the earth’s atmosphere – majorly in the stratosphere, where it is present as an ozone layer. Ozone is a pale blue gas with a pungent smell. It is less stable when compared to oxygen.
Ozone is formed from dioxygen when ultraviolet (UV) light and electrical discharges within the Earth's atmosphere.
The reaction is given below –
\[{{O}_{2}}\xrightarrow{photon}2O\]
\[{{O}_{2}}+O\to {{O}_{3}}\]
Ozone present in the atmosphere is essential for the survival of living beings as it absorbs the harmful UV radiations.
Therefore, the answer is option (d) – two forms of oxygen found in the atmosphere are Oxygen –\[{{O}_{2}}\]and Ozone – \[{{O}_{3}}\].

Additional information: Oxygen is the third-most abundant element after hydrogen and helium in the universe by mass.

Note: Both Oxygen –\[{{O}_{2}}\]and Ozone – \[{{O}_{3}}\]are made from elemental oxygen. Oxygen is called diatomic oxygen and ozone is known as triatomic oxygen.