Practice!

Sample Problem

Given that the Kf of benzene is 5.12 K∙kg/mol, and the freezing point of benzene is 278 K. What is the freezing point of benzene if 5.00 g of Na2CO3 is dissolved in 35.0 g of benzene? K

Solution

Molar mass of Na2CO3 = 106 g/mol, van’t Hoff factor = 3