Question

Which is the most abundant gas in the atmosphere?
a. Oxygen
b. Nitrogen
c. Carbon Dioxide
d. Other gases

Answer 1

Hint :Before we get into the question, let's talk about abundant gas. The term "abundant gas or substance" refers to any element or gas that is abundant in the atmosphere or how plentiful gas is present in the atmosphere. The existence of an abundant gas or element may be attributed to a variety of factors.

Complete Step By Step Answer:
Nitrogen is the most abundant gas in the Earth's atmosphere. Oxygen is the second most abundant gas. Both of these gases are made up of two atoms. The atmosphere of the Earth is made up of about 78% nitrogen, 21% oxygen, 1% argon, and trace quantities of other gases like carbon dioxide and neon. Nitrogen is found in amino acids, proteins, DNA, and RNA, among other things. Nitrogen is required for all living organisms' development, metabolic processes, and reproduction. The nitrogen is then obtained by animals consuming plants and other animals. Ammonium and nitrate can be converted to di-nitrogen by other bacteria in the soil.
All living organisms require oxygen gas $\left(O_2\right)$ for respiration, and it is a component of DNA molecules. Ozone $\left(O_3\right)$ is a type of oxygen found in the atmosphere of the Earth. By both absorbing and reflecting harmful rays, ozone protects the Earth's atmosphere from ultraviolet radiation.
Hence, from the above information we can say that the most abundant gas present in the atmosphere is Nitrogen(78%).
So, option “(b)Nitrogen” is the correct answer.

Note :
Water vapour, the most common greenhouse gas in the atmosphere, differs from other greenhouse gases in that increases in its ambient concentrations are due to the warming caused by the other greenhouse gases we release, rather than to human activities directly.