To determine molar mass from freezing point depression, we will follow the given steps:
Dissolve a known mass (wb grams) of the solute in a known mass (wa grams) of a solvent.
The molality m of this solution is:
m = (wb * 1000) / (Mb * wa);
where Mb is the unknown molar mass of the solute.
Substitute the value of m into the freezing point depression equation, and rearrange to get: Mb = (Kf * wb * 1000) / (ΔTf * wa).
Now, all you have to do is to measure the freezing point depression ΔTf, and you can determine the molar mass of any solute using the above equation.
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