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#1 sarmad

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Posted 20 May 2006 - 10:56 AM

how would you do this question, as i seem to be getting the wrong answer:

A sample of methanoic acid, HCOOHcontains 1.204 x 10^20 electrons. how many mloes of the acid is present is present in the sample?

#2 Michael

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Posted 20 May 2006 - 12:38 PM

I mole of a substance is 6.02x10^23 (Avogadros number) of any elementary particle (protons, electrons etc). So you would do 1.204x10^20 divided by 6.02x10^23 to give you 2x10^-4 moles.

#3 sarmad

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Posted 20 May 2006 - 07:59 PM

cheers, but i am sorry to tell you its wrong. its cool i worked it out , you had to devide 1.204x10^20 by
(6.02 x 10^23 multiplied with the total number of electrons in the HCOOH) which gives you 8.33 x 10^-6.
thanks anyway

#4 Michael

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Posted 20 May 2006 - 08:14 PM

Ah well, is that a higher question?

#5 sarmad

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Posted 20 May 2006 - 08:51 PM

QUOTE(Dhesi @ May 20 2006, 09:14 PM) View Post

Ah well, is that a higher question?


yeh it is, i was surprised when i saw it first its in a book a i have which is about higher calculations.

#6 Michael

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Posted 20 May 2006 - 09:06 PM

Ah damn I understand my mistake, that was stupid lol.

#7 Pyrefly

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Posted 21 May 2006 - 04:16 PM

o0 i dont get it....(yo there...someone whos about to fail chemistry here tongue.gif)

every time i try that i get 4*10^-5

care to explain to me further?





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