Problem: The density of acetonitrile (CH3 CN) is 0.786 g/mL, and the density of methanol (CH3 OH) is 0.791 g/mL. A solution is made by dissolving 23.0 mL CH3 OH in 98.7 mL CH3 CN.What is the molality of the solution? Assuming CH3OH is the solute and CH3CN is the solvent.

FREE Expert Solution

In this problem, we are being asked to calculate for the molality of the solution prepared by dissolving 23.0 mL of CH3OH in 98.7 mL of CH3CN.

 

 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 moles of solute.
Step 2: Calculate the mass of the solvent (in kg).
Step 3: Calculate the molality of the solution.


CH3OH → dissolved in CH3CN → Solute

CH3CN → where CH3OH is dissolved → Solvent


Step 1: Calculate the moles of CH3OH.

View Complete Written Solution
Problem Details

The density of acetonitrile (CH3 CN) is 0.786 g/mL, and the density of methanol (CH3 OH) is 0.791 g/mL. A solution is made by dissolving 23.0 mL CH3 OH in 98.7 mL CH3 CN.

What is the molality of the solution? Assuming CH3OH is the solute and CH3CN is the solvent.

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.