Answer:
The molar solubility of nitrogen gas is
.
Explanation:
Henry's law states that the amount of gas dissolved or molar solubility of gas is directly proportional to the partial pressure of the liquid.
To calculate the molar solubility, we use the equation given by Henry's law, which is:

where,
= Henry's constant = 
= partial pressure of nitrogen gas
Total air pressure = P = 2.71 atm
Percentage of nitrogen in air = 78.09%
Mole fraction of nitrogen ,

Putting values in above equation, we get:

Hence, the molar solubility of nitrogen gas is
.