Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: frankae on April 01, 2008, 09:56:52 AM
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Hi everyone,
The question is as follows:
"Is an aqueous solution of NaHSO4 acidic, basic or neutral? What reaction occurs with water? Calculate the pH of a 0.10 M solution of NaHSO4.
----------- THE FOLLOWING IS WRONG, I HAVE FOLLOWED UP WITH A REPLY (AND QUESTION) -------------------
I am pretty sure that the reaction with water is:
NaHSO4 + H2O -> NaOH + H2SO4
I know NaHSO4 is a weak acid, and that both products are strong acids/bases. Where do I go from here?
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Thanks in advance :)
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I am pretty sure that the reaction with water is:
NaHSO4 + H2O -> NaOH + H2SO4
I know NaHSO4 is a weak acid, and that both products are strong acids/bases.
What happens when you mix strong acid and strong base?
Do you know why sulfuric acid is called diprotic?
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NaHSO4 does not hydrolyse, this is in fact a protolysis (dissociation) of HSO4-. You should use a quadratic equation.
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I am pretty sure that the reaction with water is:
NaHSO4 + H2O -> NaOH + H2SO4
Furthermore, your reaction here isn't a good one, if you're going to guess products like this (and I guess you had to, because the instructor didn't give you a hint,) you'll have to make sure products can co-exist.
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Ok, since it dissociates, therefore:
NaHSO4 -> Na+ + HSO4-
HSO4- <-> H+ + SO42-
So therefore in aqueous solution, it is acidic. But how I do I figure out the pH of the solution, if I do not have the Ka value?
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You are on the right track.
IMHO without Ka2 you can't answer this question. pKa2 = 2.