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What titrations have you tried?

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Borek:
Please list titrations you have done during your chemistry lessons/labs. What have you titrated (vinegar) what you wanted to determine (acetic acid concentration), why your results was wrong (it was red wine vinegar and it masked phenolophtaleine). If your result was correct you may omit last point ;)

Alberto_Kravina:
This might be a quite long list, but anyway....

1.)Calculation of the titre of NaOH and HCl using oxalic acid and sodium carbonate

2.)Determination of the percentage of conc. sulfuric acid with NaOH
Result: 96,37%

3.)Determination of the percentage of Soda w = 30-50 %
Result: 37,89 % (My classmates had similar results...) We also had to draw a titration curve...easy.. ;)

4.)Determination of w[%] of a conc. Soda lye solution w = 30-35% and sodium carbonate impurities (Warder and Winkler method)
Warder method: w(NaOH)=31,67%    w(Na2CO3)= 3,85 %
Winkler method: w(NaOH)=32,20%    w(Na2CO3)= 3,45 %

4.)Determination of percentage of acetic acid in vinegar:
Nothing went wrong since it was white vinegar- Result: 4,93% (On the label it said 5% )

5.)Calculation of the titre of a KMnO4 solution: Nothing went wrong

6.)Determination of w[%](H2O2) (manganometric)
Result: w= 35,20%

6.)Determination of Nitrite in a NaCl-NaNO2 mixture
Result: 2,96%

7.)Determination of perborate (in a washing powder) and potassium persulfate (back titration)

w(Na-perborate)= 14,53 % (on the label it said "5-15%" sodium perborate)

Hmmmm..persulfate...this went wrong: it was a p.a. Potassium persulfate but my result was 88,43%. :cryss:

8.)Method Vollhardt-Wolff....It was pretty difficult to catch the endpoint. Result: 99,12% (I analyzed a p.a.MnSO4)

9.)Analysis of Ca2+ in milk with EDTA...result: 1,205 g/L Ca2+
see also: http://www.chemicalforums.com/index.php?board=8;action=display;threadid=7158

10.)Iodometry: Calculation of the titre of a thiosulfate solution with potassium iodate: nothing went wrong.

11.)Determination of H2O2 (actually the same H2O2 solution that I analyzed during manganometry)
Result: 35,91%

12.)Determination of a chlorine bleach solution:
Result: 35,47 g/L

13.)Analysis of a satured Formaldehyde solution (back titration):
Result: 36,78%

14)Argentometry: Mohr method to determine w(NaCl) in a mixture of sand and salt:
Result: 69,04%  

I performed a few others such as Reinhardt-Zimmermann method  and Haen-Low method (analysis of Copper), but there was nothing special..

Borek:
Do you have lab manuals for these (in some widely accepted and understood language ;) )?

Alberto_Kravina:

--- Quote from: Borek on March 25, 2006, 12:36:50 PM ---Do you have lab manuals for these (in some widely accepted and understood language ;) )?

--- End quote ---
I have a manual where "millions" of titrations are listed  Unfortunately this manual is written in an ununderstandable language, ( German ;) )

Borek:

--- Quote from: Alberto_Kravina on March 26, 2006, 06:42:11 AM ---I have a manual where "millions" of titrations are listed  Unfortunately this manual is written in an ununderstandable language, ( German ;) )

--- End quote ---

Paper or electronic form?

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