Answer to Question #161264 in General Chemistry for ADiyadg

Question

Calculate the grams of Magnesium Chloride that must be added to 2.91 kg of water at 149°F to lower the vapor pressure by 20 mmHg of pure water at this temperature is 188 torr. (Cl – 35 , Mg – 24)

Answer 1

For solutions that contain non-volatile solutes, the vapor pressure of the solution can be determined by using the mole fraction of the solvent and the vapor pressure of the pure solvent at the same temperature.

Mole fraction is defined as the number of moles of a component of a solution divided by the total number of moles present in that solution.