If 1 mole of a non-electrolyte solute is dissolved in 1 kg of water, what is the
Practice Questions
Q1
If 1 mole of a non-electrolyte solute is dissolved in 1 kg of water, what is the expected freezing point depression?
-1.86 °C
-3.72 °C
-0.52 °C
-2.00 °C
Questions & Step-by-Step Solutions
If 1 mole of a non-electrolyte solute is dissolved in 1 kg of water, what is the expected freezing point depression?
Correct Answer: -1.86 °C
Step 1: Understand the problem. We need to find out how much the freezing point of water will lower when we dissolve 1 mole of a non-electrolyte solute in 1 kg of water.
Step 2: Identify the formula for freezing point depression. The formula is ΔTf = Kf * m, where ΔTf is the change in freezing point, Kf is the freezing point depression constant for the solvent (water), and m is the molality of the solution.
Step 3: Find the value of Kf for water. Kf for water is 1.86 °C kg/mol.
Step 4: Calculate the molality (m). Since we have 1 mole of solute and 1 kg of water, the molality (m) is 1 mole/kg.
Step 5: Plug the values into the formula. ΔTf = Kf * m = 1.86 °C kg/mol * 1 mole/kg.
Step 6: Perform the calculation. ΔTf = 1.86 °C.
Step 7: Interpret the result. The freezing point of water will decrease by 1.86 °C when 1 mole of the solute is dissolved.
Freezing Point Depression – The decrease in the freezing point of a solvent when a solute is dissolved in it, calculated using the formula ΔTf = Kf * m.
Colligative Properties – Properties that depend on the number of solute particles in a solution, not the identity of the solute.
Molarity and Molality – Understanding the difference between molarity (moles of solute per liter of solution) and molality (moles of solute per kilogram of solvent).
