Question

Air is predominantly composed of: _______

a. O2, CO2 and CH4
b. O2, N2 and CH4
c. O2 and N2
d. O2, CO2 and H2

Answer 1

Air is predominantly composed of nitrogen and oxygen, with nitrogen accounting for 78% and oxygen about 21% of the atmosphere's composition.

Step-by-step explanation:

Air is predominantly composed of nitrogen (N₂) and oxygen (O₂). These two gases make up the vast majority of Earth's atmosphere, with nitrogen accounting for about 78% and oxygen about 21%. Although there are other gases present in trace amounts, such as carbon dioxide (CO₂), water vapor (H₂O), and methane (CH₄), their concentrations are much smaller compared to nitrogen and oxygen. The correct composition of air is primarily nitrogen and oxygen. Therefore, the answer to the question 'Air is predominantly composed of:' is c. O2 and N2.