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Topic: Molarity  (Read 6914 times)

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Offline coffee

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Molarity
« on: August 15, 2006, 08:29:56 PM »
Determine the molarity of each of the following solutions:
1) 5.23g Iron (II) nitrate in 100.0cm3 (cube) of solution
Convert 5.23 g Fe(NO)2 to moles which would equal to 0.0451 mol Fe(NO)2
Then convert 100.0cm3(cube) to liters = 0.1 L
And finally 0.0451/0.1=0.451 mol/L

Did I do this right?

Offline Will

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Re: Molarity
« Reply #1 on: August 15, 2006, 08:35:03 PM »
Did I do this right?

Not quite- nitrate is NO3- so Iron(II) nitrate would be Fe(NO3)2.
Using accurate Mrs I worked out the number of moles in the solution to be 0.02907930365, and 0.291mol/L (3sf).

Offline coffee

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Re: Molarity
« Reply #2 on: August 15, 2006, 09:12:01 PM »
omg how did i forget the 3?!  :o >o<;; lol

Thanks for helping/replying.  ;D

Offline coffee

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Re: Molarity
« Reply #3 on: August 16, 2006, 06:25:59 PM »
BTW, I got 0.315. how did you get a lower number then me?  ???

Offline Borek

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Re: Molarity
« Reply #4 on: August 16, 2006, 06:29:02 PM »
0.291M

You will not get more precise result...

CASC rulez ;)
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline Will

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Re: Molarity
« Reply #5 on: August 16, 2006, 06:33:45 PM »
BTW, I got 0.315. how did you get a lower number then me?  ???

How did you get 0.315? What did you work out the Mr of Fe(NO3)2 to be?

0.291M

Phew, it is nice to hear I got this one right from a reliable source. ;)

Offline coffee

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Re: Molarity
« Reply #6 on: August 16, 2006, 06:36:16 PM »
o nvm i got what i did wrong. lol srry   :P

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