Question

At 29.6 degrees C, pure water has a vapor pressure of 31.1 torr. A solution is prepared by adding 86.7 g of "L" a nonvolatile nonelectrolyte to 390.0 g of water. The vapor pressure of the resulting solution is 27.6 torr. Calculate the molar mass of "L"

Answer 1

Formula is:d/po=nL/nw d=31.1-27.6=3.5 po=31.1 nw=390/18=21.7moles 3.5/31.1=nL/21.7 nL=2.442moles=86.7/M M=35.5g/mol