Question

What is the vapor pressure (in torr) of a solution comprised of 220 g of ethanol (C₂H₅OH) in 870 g of H₂O at 25 °C where H₂O has a pressure of 23.76 torr?

Answer 1

mols H2O = 870/18 = about 48

mols EtOH = 220/46 = about 5 but these abouts are just estimates. You should redo these two and all calculations that follow.
total mols = 53 and
XEtOH = mols EtOH/total mols = about 5/53 = about 0.1
XH2O = about 48/53 = about 0.9
Then Psoln = XH2O x P^o_{H2O
about 0.9 x 23.76 = ?}