Forty liters (40 L) of a gas were collected over water when the barometer read 6
ID: 811057 • Letter: F
Question
Forty liters (40 L) of a gas were collected over water when the barometer read 622.0 mm Hg and the temperature was 20 degrees celcius. What volume would the dry gas occupy at standard conditions? (Hint: consider Dalton's law of partial pressure.)Show work/calculations. Forty liters (40 L) of a gas were collected over water when the barometer read 622.0 mm Hg and the temperature was 20 degrees celcius. What volume would the dry gas occupy at standard conditions? (Hint: consider Dalton's law of partial pressure.)
Show work/calculations. (Hint: consider Dalton's law of partial pressure.)
Show work/calculations.
Explanation / Answer
From table (wiki) vapour pressure of water at 20C is 2338.8 Pa.
622.0 mm Hg is (622/760)*101320 = 82922.4 Pa
Therefore, the partial pressure of the gas is 82922.4-2338.8=80583.6 Pa
moles of gas = 80583.6*0.040/(8.314*293) = 1.32 (ideal gas law is used)
therefore, the volume of dry gas at standard condition, that is at 1atm (101320 Pa) and 25C, is = nRT/P = 1.32*8.314*298/101320 = 0.03228 m^3 or 32.28L