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A chemist has one solution that is 80% acid and another solution that is 30% acid. How much of the second (30%) solution is needed to make a 400 L solution that is 62% acid?

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A chemist has one solution that is 80% acid and another solution that is 30% acid. How much of the second (30%) solution is needed to make a 400 L solution that is 62% acid?

nurali · Answer

Assume that the percentages are by volume. If we use x amount (in L) of the 30% solution, then we must use (400 - x) liters of the 80% solution in order to end up with 400 L total. The equation for this is as follows:

0.30*x + 0.80*(400 - x) = 0.62*400

This is saying that x amount of a 30% (0.30) acid solution, combined with (400 - x) amount of an 80% (0.80) acid solution, contains as much acid as is found in 400 L of a 62% (0.62) acid solution.

anonymous · Answer

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