<PRE><B>Question 481640</B>
If you have 70mL of 35% solution of acid in water, how much water would you add in order to make a 25% acid solution?
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Equation:
acid + acid = acid
0.35*70 + 0*x = 0.25(70+x)
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Multiply thru by 100 to get:
35*70 + 0 = 25*70+25x
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25x = 10*70
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x = 28mL (amt. of water needed)
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Cheers,
Stan H.</PRE>