Alyssa is a chemist with Gemco Pharmaceutical Company. She needs to prepare 12 ounces of 9% hydrochloric acid solution. The only solution she currently has available are 4% and 12% hydrocholoric acid. How much should she use of each solution to obtain the needed solution.

Answer 1

1ounce= 30ml
12x30ml =360ml
360ml x 9% = 32.4ml
4%X + 12Y(360ml-X)= 32.4ml
0.04X + 43.2ml + 0.12X = 32.4ml
0.076X = 10.8ml
x= 142.ml 4%
y = 360-142.1ml
y= 218ml 12%