A chemist has 100 ml of 25% acid solution. how much of the solution does she need to drain and replace with 70% acid solution to obtain 100

Question

A chemist has 100 ml of 25% acid solution. how much of the solution does she need to drain and replace with 70% acid solution to obtain 100 ml of 60% acid solution?

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Diễm Kiều 5 years 2021-08-27T07:14:44+00:00 1 Answers 36 views 0

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  1. Neala
    -1
    2021-08-27T07:16:36+00:00
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    Answer:

    The proportion of acid at 70% that the chemist must use will be 77.8%, while the remaining 22.2% will be acid at 25%.

    Step-by-step explanation:

    Since the chemist has 100 ml of solution with 25% acid, and wants to obtain a solution of 60% acid by mixing the first with another 70% acid solution, to determine how much of each solution the chemical should use necessary to perform the following calculation:

    70 x 1 + 25 x 0 = 70

    70 x 0.9 + 25 x 0.1 = 65.5

    70 x 0.8 + 25 x 0.2 = 61

    70 x 0.7 + 25 x 0.3 = 56.5

    Therefore, the proportion to be used is between 70% and 80% of acid at 70%, and 20% to 30% of acid at 25%.

    70 x 0.75 + 25 x 0.25 = 58.75

    70 x 0.76 + 25 x 0.24 = 59.2

    70 x 0.77 + 25 x 0.23 = 59.65

    70 x 0.78 + 25 x 0.22 = 60.1

    Thus, the proportion should be between 77 and 78% of acid at 70% and 22 and 23% of acid at 25%.

    70 x 0.778 + 25 x 0.222 = 60.01

    Thus, finally, the proportion of acid at 70% that the chemist must use will be 77.8%, while the remaining 22.2% will be acid at 25%.

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