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Author Topic: Need a formula for working out a back titration.  (Read 2556 times)

Offline Indie9999

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Need a formula for working out a back titration.
« on: 27/10/2011 17:46:58 »
Sooooo
I need the formula for working out Cerrium (IV) Suplhate molarity using titre values and standard weights.?
So I have just done a titration using Sodium Oxalate, adding a known volume of Cerrium (IV) Sulphate to excess, then back titrating with a 0.05M solution of ammonium iron (II) sulphate. Here are my weights and titre values for the first one I did.

Ammonium Iron (II) sulphate hexahydrate 3.8815g in 200mls H2SO4 (giving a molarity of 0.049491M)
Sodium Oxalate 0.1026g
First Titration (excess of unknown Cerrium (IV) Sulphate Solution) 40.15ml
second titration (0.049491M Ammonium Iron (II) sulphate) 12.3ml

Thanks for your help!


 

Offline Indie9999

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Need a formula for working out a back titration.
« Reply #1 on: 27/10/2011 18:06:16 »
I know this isn't the place to get straight up answers like this, it looks like it's a homework assignment, but it's actually something I did at work.  Today I worked out the molarity doing a potentiametric titration, I got around 0.055M, however when I search the internet for Cerrium (IV) sulphate standardisation it always points me to do a single titration with Arsnic (III) oxide (Don't have any at work!) or a back titration doing what I said above.

The titration I did today with the EV meter seem to work ok, but since I don't see any other reference to it i'm bothered that it might not be such a good result.

Hope you can see past this rather simple (for many chemists) problem and help me out!
 

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Need a formula for working out a back titration.
« Reply #1 on: 27/10/2011 18:06:16 »

 

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