# Problem: The vapor pressure of ethanol (C2H5OH) at 19˚C is 40.0 torr. A 0.900-g sample of ethanol is placed in a 2.80 L container at 19˚C. If the container is closed and the ethanol is allowed to reach equilibrium with its vapor, how many grams of liquid ethanol remain?

###### FREE Expert Solution

Calculate the mass of gas present in the container using the ideal gas equation.

$\overline{){\mathbf{PV}}{\mathbf{=}}{\mathbf{nRT}}}$

P = pressure, atm
V = volume, L
n = moles, mol
R = gas constant = 0.08206 (L·atm)/(mol·K)
T = temperature, K

91% (240 ratings)
###### Problem Details

The vapor pressure of ethanol (C2H5OH) at 19˚C is 40.0 torr. A 0.900-g sample of ethanol is placed in a 2.80 L container at 19˚C. If the container is closed and the ethanol is allowed to reach equilibrium with its vapor, how many grams of liquid ethanol remain?