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Topic: final concentration  (Read 1999 times)

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Offline whitelighter

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final concentration
« on: October 24, 2013, 11:22:27 PM »
I'm having trouble with this problem & was hoping someone could point me in the right direction:

A 6.0mL sample of 50.0% (m/v) acetic acid (HC2H3O2) solution is added to water to give a final volume of 25mL . Give the answer using 2 significant figures.

According to my text, C2 = C1 *V1/V2, so wouldn't it be 25 = 50,0 * 19/25 = 38%? However, in the online exercise, it said this was incorrect. Can someone tell me where I went wrong?

Offline Borek

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Re: final concentration
« Reply #1 on: October 25, 2013, 02:57:09 AM »
C2 = C1 *V1/V2, so wouldn't it be 25 = 50,0 * 19/25 = 38%?

No, 25 doesn't equal 38, ever.

What is C1, V1, what is C2, V2?
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Offline Vidya

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Re: final concentration
« Reply #2 on: October 25, 2013, 09:12:26 PM »

According to my text, C2 = C1 *V1/V2, so wouldn't it be 25 = 50,0 * 19/25 = 38%? However, in the online exercise, it said this was incorrect. Can someone tell me where I went wrong?

[/quote]
how did you get 19??
if C1 is 50% and V1 is 6mL
V2 is 25 mL then check the answer
what are the units required in the answer?

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