Question

What volume of ethyl alcohol and water must be mixed together to prepare 250 ml of 60% volume by volume solution of alcohol in water ?

Answer 1

let total solute content(alchohol content) in the solution be = (x) ml
and , the volume of solution = 250 ml.

therefore,
(v/v)%=( total solute content / total volume of the solution) x 100
60 = x/250 x100 
x = 150 ml


solved!

Answer 2

The concentration of the solution = 60%    (given)

The volume of the solution = 250 ml     (given)

To be found :

the volume of ethyl alcohol

We know that,

$\bf Concentration \: \:of\: \:solution=\frac{Volume \:\:of \:\:solvent}{Volume\:\: of\:\: solution}\times100$

Let the volume of ethyl alcohol be x ml

So,

$\bf Concentration\:\:of\:\:solution=\frac{volume\:\:of \:\:solvent(ethyl\:\:alcohol)}{Volume \:\:of \:\:solution}\times 100$

⇒ $\bf 60=\frac{x}{250}\times100$

⇒ $\bf \frac{60\times250}{100}=x$

⇒ $\bf 150=x$

∴ Therefore

the volume of ethyl alcohol in water is 150 ml