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Topic: A mole question that has me confused.  (Read 3609 times)

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Offline bmack

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A mole question that has me confused.
« on: April 22, 2007, 10:26:43 PM »


 The question is :
Given that 14N is 99.63%abundance, and 15N is .37% abundance. What is the weight in grams of 1 mole of naturally accuring Nitrigen?

I really do not know how to solve. :(

Offline enahs

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Re: A mole question that has me confused.
« Reply #1 on: April 22, 2007, 11:18:06 PM »
This is nothing more then a weighted average basic math question.
http://dbhs.wvusd.k12.ca.us/webdocs/Mole/AverageAtomicWeight.html
http://www.mathwords.com/w/weighted_average.htm

Really, it is more then likely an equation in your book in bold letters or outlined in some color. Probably in one of the first 3 chapters.



Offline Yggdrasil

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Re: A mole question that has me confused.
« Reply #2 on: April 23, 2007, 01:31:28 AM »
In a mole of nitrogen, how many moles of nitrogen-14 do you have?  How much would this amount of nitrogen-14 weigh?  How many moles of nitrogen-15 would you have?  How much would this weigh?

Offline bmack

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Re: A mole question that has me confused.
« Reply #3 on: April 23, 2007, 04:44:20 PM »
14 grams is the answer. Thank you.  I think...no, I know I make this harder than it has to be. :-[

Offline Borek

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Re: A mole question that has me confused.
« Reply #4 on: April 23, 2007, 04:54:02 PM »
Be carefull about significant digits here.
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