Chemical Forums
Chemistry Forums for Students => High School Chemistry Forum => Topic started by: kuromi on May 11, 2009, 07:25:05 AM
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C6H8O7 (aq) + OH- (aq) :rarrow: C6H7O7- (aq) + H2O(l)
OR C6H8O7 (aq) + 3OH- (aq) :rarrow: C6H5O7 3- (aq) + 3H2O(l)
Which one is correct ??
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Both, plus
C6H8O7 + 2OH- :rarrow: C6H6O72- + 2H2O
Depends on what you are asking (or are asked) about.
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Both, plus
C6H8O7 + 2OH- :rarrow: C6H6O72- + 2H2O
Depends on what you are asking (or are asked) about.
to determine the Ka and pKa of 0.1M citric acid !!
at 296 K , 20cm^3 of 0.1M citric acid titrate with 0.1M sodium hyoxide until end pt.
then , add a further 20cm^3 of the same acid
the pH of the mixture is 4.45 and used 62.7 cm^3 of sodium hyoxide ~~~
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to determine the Ka and pKa of 0.1M citric acid !!
pKa1, pKa2 or pKa3?
at 296 K , 20cm^3 of 0.1M citric acid titrate with 0.1M sodium hyoxide until end pt.
Just out of curiosity - how do you determine end point?
then , add a further 20cm^3 of the same acid
the pH of the mixture is 4.45 and used 62.7 cm^3 of sodium hyoxide ~~~
What will you have in the solution at this point?
Think about stoichiometry of the neutralization reaction. You already known citric acid is triprotic.
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this is
to determine the Ka and pKa of 0.1M citric acid !!
pKa1, pKa2 or pKa3? --- > i dont know , lab sheet is just to ask the pKa !!
i used phenolphthalein --> end pt : colourless to pink
the pH of the mixture is 4.45 and used 62.7 cm^3 of sodium hyoxide for titration,
which are my experimental results !!
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So, when the solution turns pink, what does that mean? Is there any acid left? What would it mean, to a citric acid molecule, if it had no acid left? What is acid, anyway?
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lab sheet is just to ask the pKa !!
No such thing as just pKa of the citric acid. It has to be one of the three.