Question 278478:  To prepare two liters of a 10% solution from a pure drug, you would need ____? 
 Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! To prepare two liters of a 10% solution from a pure drug, you would need ____? 
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Equation: 
Let x be the amount of water you add. 
pure drug + water = 10% mix 
1.00(2-x) + 0(x) = 0.10*2 
Multiply thru by 100 to get: 
100*2 - 100x + 0 = 10*2  
-100x = -90*2 
x = 1.8 liters  (amt. of water needed for the mixture 
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2-x = 0.2 liters (amt. of pure drug needed for the mixture 
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Cheers, 
Stan H. 
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