You can put this solution on YOUR website! How much water must be evaporated from 200 mL of a 5% salt solution to produce a 25% salt solution?
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Equation:
water - water = water
0.95*200 - 1*x = 0.75(200-x)
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95*200 - 100x = 75*200 - 75x
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25x = 20*200
x = (4/5)200 = 160 mL (amt. of water to evaporate)
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Cheers,
Stan H.
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