Answer:
Mass of nitrogen gas dissolved= 1.1732 grams
Step-by-step explanation:
According to Dalton's Law of partial pressure:

Where,
is the partial pressure of nitrogen
is the Total pressure
is the mole fraction of nitrogen
Given :
Total pressure = 1.0 atm
Mole fraction of nitrogen = 0.78
Partial pressure of nitrogen:

Partial pressure of nitrogen = 0.78 atm
According to Henry's law:
Solubility = Henry's constant (k)×Partial pressure
k = 6.26×10⁻⁴ mol/L-atm
Thus,
Solubility of nitrogen = 6.26×10⁻⁴ mol/L-atm×0.78 atm = 4.8828×10⁻⁴ mol/L
Given: Volume = 86.0 L
So, Moles of nitrogen gas dissolved:
Moles = Solubility (Concentration dissolved)×Volume
Moles = 4.8828×10⁻⁴ mol/L×86.0 L = 0.0419 moles
Also,


Molar mass of nitrogen gas = 28 g/mol
So,
Mass of nitrogen gas dissolved = 0.0419 moles×28 g/mol = 1.1732 grams