Question 469851
How much pure alcohol must be added to 25 mL of water to produce 50% alcoholic solution?
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Equation:
alcohol + alcohol = alcohol
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x + 0*25 = 0.5(x+25)
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Multiply thru by 100
100x + 0 = 50x+50*25
50x = 50*25
x = 25mL (amt. of pure alcohol needed)
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Cheers,
Stan H.