# A chemist has a solution that is 20% hydrochloric acid (hcl) and a solution that is 50% hcl. how much of each solution should be mixed to obtain 300 cubic centimeters (cc) of a solution that is 30% hcl?

Jun 9, 2017

#### Explanation:

First acid (20%), amount V (which is volume (in cc))
Second acid (50%), amount $300 - V$

Now compute the amounts (volumes)

$0.30 \times 300 = 0.20 \times V + 0.50 \times \left(300 - V\right)$

$90 = 0.2 V + 150 - 0.5 V$
$90 - 150 = - 0.3 V$
$- 60 = - 0.3 V$

$V = 200$ cc (from 20% HCl)

The rest (100 cc) should be taken from 50% HCl solution.

Your answer is 200 cc from 20% HCl and 100 cc from 50% HCl solution will do.