Moles of gas = 0.369
Further explanation
Given
P = 2 atm
V = 5.3 L
T = 350 L
Required
moles of gas
Solution
Ideal gas Law
Avogadro's law : at the same temperature and pressure, the ratio of gas volume will be equal to the ratio of gas moles
moles of O₂ = 45% x 0.369 = 0.166
moles of Ar = 12% x 0.369 = 0.044
moles of N = 43% x 0.369 = 0.159