Question

Benzene has a vapor pressure of 100.0 Torr at 26°C. A nonvolatile, nonelectrolyte compound was added to 0.309 mol benzene at 26°C and the vapor pressure of the benzene in the solution decreased to 60.0 Torr. What amount (in moles) of solute molecules were added to the benzene?

Answer 1

Isn't delta P = X_soluteP^o_solvent

Answer 2

That is what I tried using...I solved for m for when P= 100 Torr, then used that to set up an equation when P=60 Torr to find the difference, but my answer is consistently incorrect. I am setting up the algebra incorrectly but am not sure what I am missing

Answer 3

This is not a molality problem. I think I've taken care of this problem further up the board.