Determining Freezing Point of Aqueous Solution
What is the freezing point of the solution?
The freezing point of water is 0 °C, the freezing point of the solution is:
Freezing point of solution = 0 °C - 2.79 °C = -2.79 °C
The freezing point of the solution is -2.79 °C.
Answer:
The freezing point of the solution is -2.79 °C.
To determine the freezing point of the solution from the given data, we can use the formula:
ΔTf = Kf × m
where:
ΔTf is the change in freezing point (°C)
Kf is the molal freezing-point constant of water (1.86 °C/mol)
m is the molality of the solution (mol/kg)
The molality of the solution is calculated by dividing the number of moles of solute by the mass of solvent in kilograms. Given that the solution contains 0.15 moles of solute and 100 grams of solvent:
The molality of the solution is m = 0.15 moles / 0.1 kg = 1.5 mol/kg
Substituting this value into the equation, we get: ΔTf = 1.86 °C/mol × 1.5 mol/kg = 2.79 °C