document.write( "Question 629163: I need to make a 20% solution of alcohol. I have on hand 70% alcohol. What formula do I use to dilute the 70% into 20% using sterile H2O? \n" ); document.write( "

Algebra.Com's Answer #396075 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi,
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document.write( "dilute the 70% alcohol solution into 20% alcohol solution using sterile H2O
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document.write( "  water = water
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document.write( " x + .30A = .80(A+x)
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document.write( "      .20x = .5A
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document.write( "         x = .5A/.2
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document.write( "         x = 2.5A     Add 2.5 times as much water as the amount of 70% solution used\r
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document.write( "For ex:  using 10L of 70% solution  ⇒  
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