Question

A 230.0-mL sample of a 0.275 M solution is left on a hot plate overnight; the following morning the solution is 1.15 M. What volume of solvent has evaporated from the 0.275 M solution?

Answer 1

Answer: The volume of solvent evaporated is 173.57 mL

Step-by-step explanation:

`\text{Molarity of the solution}=\frac{\text{Moles of solute}* 1000}{\text{Volume of solution (in mL)}}` .....(1)

Molarity of solution = 0.275 M

Volume of solution = 230.0 mL

Putting values in equation 1, we get:

`0.275M=\frac{\text{Moles of solution}* 1000}{230.0}\\\\\text{Moles of solution}=(0.275* 230)/(1000)=0.0632mol`

As, the moles of solution remains the same.

When solvent gets evaporated, the volume of the solution is calculated by using equation 1:

Moles of solution = 0.0632 moles

Molarity of the solution = 1.15 M

Putting values in equation 1, we get:

`1.15=\frac{0.0632* 1000}{\text{Volume of solution}}\\\\\text{Volume of solution}=(0.0632* 1000)/(1.15)=56.43mL`

Volume of solution evaporated = (230.0 - 56.43) mL = 173.57 mL

Hence, the volume of solvent evaporated is 173.57 mL

Answer 2

As

M1V1=M2V2

so (230)(.275) = (1.15)(x) x = 63.25/(1.15) x = 55 mL