A chemist wishes to mix a solution that is 12 % acid. She has on hand 14 liters of a 6 % acid solution and wishes to add some 16 % acid solution to obtain the desired 12 % acid solution. How much 16 % acid solution should she add?

25 liters of the 16% solution should be added.

Step by Step Explanation:

pure acid amount + pure acid amount = total pure acid amount

So,

0.02*10 + 0.16*x = 0.12 * (10+x)

0.02*10 + 0.16x = 0.12*10 + 0.12*x

0.16*x - 0.12*x = 0.12*10 - 0.02*10

(0.16 - 0.12) * x = 0.12*10 - 0.02*10

x = (0.12*10-0.02*10) / (0.16-0.12) = 25

Check: (0.2*10+0.16*25) / (10+25) = 0.12 = 12% of concentration of the final mixture.! Correct!