SOLUTION: how many milliliters of a 10% hydrogen peroxide solution and how many milliliters of a 2% hydrogen peroxide solution should be mixed to obtain 500 mL if a 4% hydrogen peroxide solu

Question 929629: how many milliliters of a 10% hydrogen peroxide solution and how many milliliters of a 2% hydrogen peroxide solution should be mixed to obtain 500 mL if a 4% hydrogen peroxide solution?

Found 2 solutions by stanbon, Alan3354:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
how many milliliters of a 10% hydrogen peroxide solution and how many milliliters of a 2% hydrogen peroxide solution should be mixed to obtain 500 mL if a 4% hydrogen peroxide solution?
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Equation:
hydro + hydro = hydro
0.02x + 0.10(500-x) = 0.04*500
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2x + 10*500 - 10x = 4*500
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-8x = -6*500
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x = (3/4)500
x = 3*125 = 375 ml (amt. of 2% solution needed)
500-x = 125 ml (amt. of 10% solution needed)
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Cheers,
Stan H.
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Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Do it like this one. Only the numbers are different.
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Amanda wants to make 8 gal. of a 20% saline solution by mixing together a 56% saline solution and a 8% saline solution. How much of each solution must she use?
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e = amount of 8%
f = amount of 56%
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e+ f = 8 (total solution)
8e + 56f = 20*8 (total saline)
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e+ f = 8
e + 7f = 20
------------ Subtract
-6f = -12
f = 2
e = 6
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