1. A solution contains of 10.3 g of glucose (C6 H12O6 ) dissolved in 250 g of water.
What is the freezing point depression of the solvent?
mass of solute = 10.3 g
mass of solvent = 250 g = 0.250 kg
solute: glucose (C₆H₁₂O₆)
solvent: water (H₂O)
Step 1: Calculate the molar mass of solute.
molar mass of solute = (12.01 g/mol × 6) + (1.008 g/mol × 12) + (16.00 g/mol × 6)
molar mass of solute = 180.156 g/mol
Step 2: Calculate the number of moles of solute.
Step 3: Calculate the molality of solution.
Step 4: Calculate the freezing point depression.
Note: The value of Kf for water is 1.86°C/molal.