# 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

###### 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.

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the The Colligative Properties concept. You can view video lessons to learn The Colligative Properties. Or if you need more The Colligative Properties practice, you can also practice The Colligative Properties practice problems.