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PPM QUESTION


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#1 slow loris

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Posted 15 December 2016 - 04:39 AM

Hello!

 

I have this question in my textbook, in which I know the answer, yet I cannot figure out how to obtain it: The air has helium 0,0007% (m/m). Convert this concentration into ppm.

 

The answer should be 0,7ppm.

 

Thank you for reading this!


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#2 _Rick_

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Posted 15 December 2016 - 04:47 AM

Parts per million

 

0.00007% means  0.00007 per 100 (percent)    

 

Thusly 0.00007/100 = 0.0000007

0.0000007 * 1000000 = 0.7 Parts per million


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#3 slow loris

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Posted 15 December 2016 - 04:51 AM

Thank you so much! I haven't thought of that kind of method. That will help me with a whole bunch of upcoming stuff, I really appreciate it.


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#4 hypervalent_iodine

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Posted 15 December 2016 - 04:53 AM

I don't think the answer given is correct. Ppm is parts per million. From a percentage concentration, calculating ppm is just a matter of multiplying by 10000 (since % is parts per hundred). Given that, and assuming you've provided the correct number as per the question, I get 7ppm. Can you check that the question states 0.0007% and not 0.00007%?

Parts per million
 
0.00007% means  0.00007 per 100 (percent)    
 
Thusly 0.00007/100 = 0.0000007
0.0000007 * 1000000 = 0.7 Parts per million


This is correct, but the OP doesn't give 0.00007% as the value.
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#5 slow loris

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Posted 15 December 2016 - 04:57 AM

The question states 0,00007%, and the answer says 0,7ppm. 


Sorry I did a typo earlier and typed 0,0007 instead of 0,00007. Thanks for your help so much though!


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#6 FrankP

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Posted 21 December 2016 - 10:11 PM

Parts per million

 

0.00007% means  0.00007 per 100 (percent)    

 

Thusly 0.00007/100 = 0.0000007

0.0000007 * 1000000 = 0.7 Parts per million

 

This was prob the easiest way anyone could have explained this nice job. I have favorited this for future use by myself as well. I know I will end up needing this down the road. 


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