Answer:
Volume at STP = 0.1401 L
Explanation:
We are given:
Vapor pressure of water = 20 torr
Total vapor pressure = 753 torr
Vapor pressure of gas = Total vapor pressure - Vapor pressure of water = 753 torr - 20 torr = 733 torr
Using
[tex]PV=nRT[/tex]
where,
P = pressure of the gas = 733 torr
V = Volume of the gas = 157 mL= 0.157 L
T = Temperature of the gas = [tex]22^oC=[22+273]K=295K[/tex]
R = Gas constant = [tex]62.3637\text{ L.torr}mol^{-1}K^{-1}[/tex]
n = number of moles of gas = ?
Putting values in above equation, we get:
[tex]733 torr\times 0.157L=n\times 62.3637\text{L.torr}mol^{-1}K^{-1}\times 295K\\\\n=\frac{733\times 0.157}{62.3637\times 295}=0.006255mol[/tex]
At STP, one mole of the gas occupies a volume of 22.4 L
So, 0.006255 mole of the gas occupies a volume of 22.4*0.006255 L
Volume at STP = 0.1401 L
