Question

Will someone please help me calculate the volume of methanol necessary to make 762 ml of a 18.7% v/v methanol solution.

Answer 1

This simply means 18.7% of the volume of the solution is made up of methanol.
The rest (81.3%) is just water which you fill till you reach 762 mL.

So find 18.7% of 762 ml solution.

Answer 2

In general, if a solution is made up of two solvents A, and B, then the % v/v composition is of solvent A is simply = volume solvent A / total volume solution

Answer 3

You can also think of it by it's mathematical definition: \(\sf \large \color{red}{ (\frac{volume ~of ~solute}{volume ~of ~solution}) x 100 }\)