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Question

a laboratory technician needs to make a 117 liter batch of a 20% acid solution how can the laboratory technician combined a batch of acid solution that is pure acid with another that is 10% to get the desired concentration? How many liters of pure acid and how many liters of 10% acid solution get the desired concentration?

Answer 1

x = liters of the 10% acid

117 - x = liters of the 100% acid

 

(10%)x + (100%)(117 - x) = (20%)(117 L)

 

10x + 100(117 - x) = 20(117)

x + 10(117 - x) = 2(117)

-9x = -936

 

x = 104 L

117 - x = (117 - 104) L = 13 L