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Topic: Stock solution and percentage by mass  (Read 14206 times)

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Kdub

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Re:Stock solution and percentage by mass
« Reply #15 on: October 13, 2005, 01:27:11 PM »
need to get this question!

Offline Borek

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Re:Stock solution and percentage by mass
« Reply #16 on: October 13, 2005, 02:05:38 PM »
So start from both correct equations, you know how to do the math - DO IT!
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Kdub

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Re:Stock solution and percentage by mass
« Reply #17 on: October 13, 2005, 02:46:12 PM »
I keep getting moles in the negatives...but I don't know where my mistake is:
55.85x + 26.98y = 3.753
55.85(0.1456 - 2/3y) + 26.98y = 3.753
8.132 - 37.233y + 26.98y = 3.753
-10.253y = -4.379
           y = 0.4271

x + 2/3y = 0.1456
x + 2/3(0.4271) = 0.1456
x + 0.2847 = 0.1456
              x = -0.1391 ... theres the mistake... ???

Offline Borek

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Re:Stock solution and percentage by mass
« Reply #18 on: October 13, 2005, 03:02:51 PM »
Second equation should be

x + 3/2y = 0.1456

Sorry, you are making mistakes faster than I can correct them.
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Kdub

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Re:Stock solution and percentage by mass
« Reply #19 on: October 13, 2005, 05:32:28 PM »
44.5% finally ;D

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