Question 489801: How much water must be evaporated from 32oz of a 4% solution to make a 6% salt solution? Found 2 solutions by chessace, josmiceli:Answer by chessace(471) (Show Source):
You can put this solution on YOUR website! As usual, ans = x = H2O to go into thick air.
Salt is same quant before and after: 0.06 * (32 -x) = 0.04 * 32
*100, subtract righhand side:
6*32 -6x = 4*32
6x = (6-4)*32
x = 32/3
Taking away a third is exactly what you would expect: The remaining thirds have to split the extra 4% salt 2 ways, 4 + 4/2 = 6.
You can put this solution on YOUR website! The key is that you have as much salt after evaporation as before
In words:
(ounces of salt)/(total salt + water solution at end) = 6%
given: ounces of salt at start ounces of water at start
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Let = ounces of water to be evaporated
10.667 ounces of water must be evaporated
check:
That leaves ounces of water
OK