Problem: A 2.800x10-2 M solution of NaCl in water is at 20.0° C. The sample was created by dissolving a sample of NaCl in water and then bringing the volume up to 1.000 L. It was determined that the volume of water needed to do this was 999.2 mL. The density of water at 20.0° C is 0.9982 g/mL.Calculate the molality of the salt solution.

FREE Expert Solution

We’re being asked to calculate for the 2.800x10-2 M solution of NaCl

When calculating for molality, we use the following equation:

molality(m) = mol solutekg solvent


We will calculate the molality of the solution using the following steps:

Step 1: Calculate the mass of the solute.

Step 2: Calculate the mass of the solution.

Step 3: Calculate the mass of the solvent (in kg).

Step 4: Calculate the molality of the solution.

Solute → NaCl

Solvent → water (H2O)


100% (339 ratings)
View Complete Written Solution
Problem Details

A 2.800x10-2 M solution of NaCl in water is at 20.0° C. The sample was created by dissolving a sample of NaCl in water and then bringing the volume up to 1.000 L. It was determined that the volume of water needed to do this was 999.2 mL. The density of water at 20.0° C is 0.9982 g/mL.


Calculate the molality of the salt solution.

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 Molality concept. You can view video lessons to learn Molality. Or if you need more Molality practice, you can also practice Molality practice problems.