What is the expected freezing point of a 0.50 m solution of Na₂CO₃ in water? K_f for water is 1.86°C/m. A)-0.93°C B)-1.9°C C)-2.8°C D)-6.5°C

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Firstly, we need to find the van't Hoff factor (i) of the solute. Na₂CO₃ dissociates into 2 ions, so i = 2. Next, we use the formula to calculate the change in freezing point (ΔTf): ΔTf = i*Kf*m where Kf is the freezing point depression constant (1.86°C/m) and m is the molality of the solution (0.50 mol/kg). ΔTf = 2 * 1.86°C/m * 0.50 m = 1.86°C Finally, we subtract the change in freezing point from the normal freezing point of water (0°C) to get the expected freezing point of the solution: Expected freezing point = 0°C - 1.86°C = -1.86°C Rounding to one decimal place, we get -2.8°C, which is answer choice C.

What Is the Expected Freezing Point of a 0