Question

Brooke needs 360 milliliters of a 53% acid solution for a chemistry experiment. She has two acid solutions, A and B, that can be mixed together to form the solution. Solution A is 50% acid, and Solution B is 60% acid. How much of each solution should she use to create the mixture?

She should use ____ milliliters of Solution A.

She should use ____ milliliters of Solution B.

Answer 1

Let A and B be the mL of each solution needed.

quantity equation
A + B = 360
concentration equation
0.5A + 0.6B = 0.53(360)

use A = 360 - B for substitution in the other equation.

0.5(360 - B) + 0.6B = 190.8
180 - 0.5B + 0.6B = 190.8
180 + 0.1B = 190.8
0.1B = 190.8 - 180
0.1B = 10.8
B = 10.8/0.1
B = 108 mL

then A+B = 360
A + 108 = 360
A = 360 - 108
A = 252 mL