Practice Problem: Colligative Properties

The video tutorial explains colligative properties, focusing on boiling point elevation and freezing point depression. It provides step-by-step calculations for determining the boiling point of a benzene solution and the freezing point of an NaCl solution. The tutorial emphasizes the importance of understanding molality and the dissociation of solutes in solutions.

What is the boiling point of pure benzene?

• 85.0 degrees Celsius

• 82.3 degrees Celsius

• 80.1 degrees Celsius

• 78.5 degrees Celsius

Which formula is used to calculate the change in boiling point?

• Delta TF = KF * molality

• Delta TB = KF * molality

• Delta TF = KB * molality

• Delta TB = KB * molality

What is the boiling point elevation for a 0.33 molal benzene solution?

• 0.53 degrees Celsius

• 0.83 degrees Celsius

• 0.73 degrees Celsius

• 0.93 degrees Celsius

What happens to NaCl when it is dissolved in water?

• It evaporates

• It dissociates into sodium and chloride ions

• It forms a precipitate

• It remains as NaCl molecules

What is the molar mass of NaCl used in the calculation?

• 58.4 grams per mole

• 57.2 grams per mole

• 55.3 grams per mole

• 60.5 grams per mole

How is molality defined?

• Moles of solute per liter of solution

• Moles of solute per kilogram of solvent

• Grams of solute per kilogram of solvent

• Grams of solute per liter of solution

What is the new freezing point of the NaCl solution?

• -4.0 degrees Celsius

• -1.0 degrees Celsius

• -2.0 degrees Celsius

• -3.0 degrees Celsius