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Topic: Conversion from ppt to ppm  (Read 12716 times)

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Goddess

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Conversion from ppt to ppm
« on: May 25, 2005, 07:07:38 PM »
 I need help with a concentration problem:

"A 0.264 g sample of steel containing 8 ppt Cr (ppt = parts per 1000) was dissolved in nitric acid and diluted to 1 L with water. What is the ppm concentration of Cr3+ in the resulting solution?"

My work:

2.64x10^-5 kg steel    x   8 g Cu   x   10^6 ?g  x    1   
                          Kg steel            g            1000ml

=.2112  ?g/ml



The units come out right but I know the answer is wrong.  Am I missing a step or am I completely off base?

Offline Borek

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Re:Conversion from ppt to ppm
« Reply #1 on: May 25, 2005, 07:31:51 PM »
?g/ml

It is ppt, not ppm. ppm is ?g/L.
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Goddess

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Re:Conversion from ppt to ppm
« Reply #2 on: May 25, 2005, 07:40:18 PM »
I'm sorry, I should have indicated that he wants the answer in ?g/ml.  The problem does say ppm but his units for the answer are as above.

Have I done the calculation right then?

Thanks for the *delete me*

Offline Borek

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Re:Conversion from ppt to ppm
« Reply #3 on: May 25, 2005, 07:54:09 PM »
0.264 g is not 2.64x10^-5 kg. 2112 are proper digits, the point is: where point should be? ;)
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Goddess

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Re:Conversion from ppt to ppm
« Reply #4 on: May 25, 2005, 07:59:26 PM »
Oh crap.  I'll be the one with the dunce cap on in the corner.   :P




Thanks for your *delete me*

Garneck

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Re:Conversion from ppt to ppm
« Reply #5 on: May 30, 2005, 02:54:51 PM »
It's ppth, not ppt.

ppt = part per trillion (1012)

asqa

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Re:Conversion from ppt to ppm
« Reply #6 on: July 27, 2005, 05:57:45 AM »
It is ppt, not ppm. ppm is ?g/L.

sorry borek
ppm is parts per million is mg/L or ?g/ml
?g/L is ppb i.e. parts per billion



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Re:Conversion from ppt to ppm
« Reply #7 on: July 27, 2005, 06:30:31 AM »
ppm is parts per million is mg/L or ?g/ml
?g/L is ppb i.e. parts per billion

Sorry, my mistake. I know where it did started - g/L is not 1, it is ppt already :(
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