Practice: How many moles of ethylene glycol, C2H6O2, must be added to 1,000 g of water to form a solution that has a freezing point of – 10ºC?
Freezing Point Depression is the phenomenon when adding a solute to a pure solvent results in decreased freezing point of the solvent.
Concept #1: Freezing Point Depression
Example #1: Calculate the freezing point of a solution containing 110.7 g glucose, C6H12O6, dissolved in 302.6 g water.
Practice: How many moles of ethylene glycol, C2H6O2, must be added to 1,000 g of water to form a solution that has a freezing point of – 10ºC?
Practice: An ethylene glycol solution contains 28.3 g of ethylene glycol, C2H6O2 in 97.2 mL of water. Calculate the freezing point of the solution. The density of water 1.00 g/mL.
Practice: When 825 g of an unknown is dissolved in 3.45 L of water, the freezing point of the solution is decreased by 2.89ºC. Assuming that the unknown compound is a non-electrolyte, calculate its molar mass.
