Question

A volatile liquid is evaporated in a flask in a boiling a water bath (

Temperature = 100°C) with a volume of 297ml. The evaporated gas is
condensed in the flask and it is found to have a mass of 0.435g.
Atmospheric pressure for that day is 765mmHg. What is the Molar Mass of
the Volatile liquid? Show work

Answer 1

Molecular Weight of gas = 44.418 grams/mole

Step-by-step explanation:

PV = nRT = (mass/f.wt.)RT => f.wt. = mass·R·T/P·V

mass = 0.435g

R = 0.08206·L·atm/mol·K

T = 100°C = 372K

P = (765/760)Atm = 1.01Atm

V = 297ml = 0.297L

f.wt. = (0.435g)(0.08206L·Atm/mol·K)(372K)/(1.01Atm)(0.297L) = 44.418 grams/mole