# Question 3ab39

Jul 31, 2017

The volume is $= 25.7 m l$

#### Explanation:

Let volume of pure acid (30%) be $= v m l$

Then,

Volume of (100%)# acid is $= \left(60 - v\right) m l$

The mass balance equation with respect to the acid is

$30 v + 100 \left(60 - v\right) = 70 \cdot 60$

Solving this equation for $v$

$30 v + 6000 - 100 v = 4200$

$\left(100 - 30\right) v = 6000 - 4200$

$70 v = 1800$

$v = \frac{1800}{70} = 25.7 m l$