SOLUTION: A chemist needs to mix a solution that is 34% silver nitrate with one that is 4% silver nitrate to obtain 100 milliliters of a mixture that is 7% silver nitrate. How many millilite

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Question 254408: A chemist needs to mix a solution that is 34% silver nitrate with one that is 4% silver nitrate to obtain 100 milliliters of a mixture that is 7% silver nitrate. How many milliliter of each of the solutions must be used?
Found 2 solutions by ankor@dixie-net.com, checkley77:
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
A chemist needs to mix a solution that is 34% silver nitrate with one that is 4% silver nitrate to obtain 100 milliliters of a mixture that is 7% silver nitrate.
How many milliliter of each of the solutions must be used?
:
Let x = amt of 34% solution required
It states that the resulting amt is to be 100 ml, therefore
(100-x) = amt 4% solution
:
Write an "amt of silver nitrate" equation
.34x + .04(100-x) = .07(100)
:
.34x + 4 - .04x = 7
.34x - .04x = 7 - 4
.3x = 3
x =
x = 10 ml of 34% solution
and
100 - 10 = 90 ml of 4% solution
;
:
Check solution:
.34(10) + .04(90) = .07(100)
3.4 + 3.6 = 7

Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website!
.34x+.04(100-x)=.07*100
.34x+4-.04x=7
.30x=7-4
.30x=3
x=3/.30
x=10 ml. of 34% solution is used.
100-10=90 ml. of 3% solution is used.
Proof:
.34*10+.04*90=7
3.4+3.6=7
7=7