Question

A chemist wishes to mix a solution that is 12% acid. She has on hand 6 liters of a 4% 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?
Complete the table.
Liters of
Solution
Percent Acid Liters of
(as a decimal) Pure Acid
0.04
6
Х
0.16
0.12

Answer 1

Answer:

25 liters of the 16% solution should be added.

Step-by-step explanation:

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

0.02*10          + 0.16*x           = 0.12*(10+x)     <<<---=== it is your balance equation;  x is the amount (in liters) of the 16% solution.

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 = %280.12%2A10-0.02%2A10%29%2F%280.16-0.12%29 = 25.

Answer.  25 liters of the 16% solution should be added.

Check.   %280.02%2A10+%2B+0.16%2A25%29%2F%2810+%2B+25%29 = 0.12 = 12% of concentration of the final mixture.   ! Correct !