Answer:
The number of moles of H₂ is 0.01135 moles
The partial pressure of H₂ in the balloon is 0.975 atm
Explanation:
From Dalton's law of partial pressure, we have;
Total pressure = Pressure of H₂ + Pressure of the water vapor
The vapor pressure of water at 20°C = 17.5 mmHg = 0.0230225 atm
For equilibrium, pressure of the balloon = Surrounding pressure = Atmospheric pressure
∴ Pressure of H₂ + Pressure of the water vapor = Atmospheric pressure
Partial pressure of H₂ in the balloon, P = 0.998 - 0.0230225 = 0.9749775 ≈ 0.975 atm
0.975 atm = 98789.595 Pa
Volume of balloon, V = 0.28 L
n = PV/(RT)
Where:
R = Universal gas constant = 0.08205 L·atm/(mol·K)
T = Temperature = 20°C = 293.15 K
∴ n = 0.975 * 0.28/ (0.08205 * 293.15) = 0.01135 moles.
