The vapour pressure of acetone at 20^oC is 185 torr. When 1.2 g of a non-volatile substance was dissolved in 100 g of acetone at 20^oC, its vapour pressure was 183 torr. The molar mass (g mol^-1) of the substance is:

Consider separate solutions of 0.500 M C₂H₅OH(aq), 0.100 M Mg₃(PO₄)₂(aq), 0.250 M KBr(aq) and 0.125 M Na₃PO₄(aq) at 25^oC. Which statement is true about these solutions, assuming all salts to be strong electrolytes?

K_f for water is 1.86K kg mol^–1. If your automobile radiator holds 1.0 kg of water, how many grams of ethylene glycol (C₂H₆O₂) must you add to get the freezing point of the solution lowered to –2.8^oC ?

Ethylene glycol is used as an antifreeze in a cold climate. Mass of ethylene glycol which should be added to 4 kg of water to prevent it from freezing at −6^oC will be : [K_f for water = 1.86 K kg mol⁻¹ , and molar mass of ethylene glycol = 62 g mol⁻¹ )