# Problem: A solution prepared by dissolving 3.27 g of a nonvolatile, covalent solute in 30.0 g of water boils at 100.74 °C. What is the approximate molar mass of the solute? K bp H 2O = 0.512 oC/m.

###### FREE Expert Solution

We’re being asked to list the given aqueous solutions in order of increasing boiling points.

Recall that the boiling point of a solution is higher than that of the pure solvent and the change in boiling point (ΔT­b) is given by:

The change in boiling point is also related to the molality of the solution:

$\overline{){{\mathbf{\Delta T}}}_{{\mathbf{b}}}{\mathbf{=}}{{\mathbf{imK}}}_{{\mathbf{b}}}}$

where:

i = van’t Hoff factor

m = molality of the solution (in m or mol/kg)

Kb = boiling point elevation constant (in ˚C/m) of the solvent

We go through the following steps to solve the problem:

Step 1. Calculate the molality of the solution

Step 2. Calculate the moles of solute

Step 3. Calculate the molar mass

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###### Problem Details

A solution prepared by dissolving 3.27 g of a nonvolatile, covalent solute in 30.0 g of water boils at 100.74 °C. What is the approximate molar mass of the solute? K bp H 2O = 0.512 oC/m.