I understand that C5H5N is a weak base and that HClO2 is a weak acid. I just don't know how to determine if it is acidic or basic.
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Sorry. Are we supposed to know which of the several compounds the elemental formula C5H5N refers to? Why would you think that? If you understood anything about chemistry, that is.
So, lets assume its pyridine and not diethynemethyl amine nor cyclopentadienyl imine (I could possibly come up with a few others ...)
So your question is given the salt of a weak acid and a weak base how do you determine if the salt is acidic or basic?
pKa PyrH(+) = 5.25
pKa Chlorous Acid =1.96
In this situation it is clear that the salt will be acidic based on the Ka's.
The Ka or Kb is a measure of the tendency of the reaction HA +H2O → A(-) +H3O(+) or equivalently
B(+) + OH(-) ←BOH
There are several ways to calculate the pH of solutions but the way I look at it
given that chlorous acid is 'mostly' dissociated will the pyridine suck up so much of the H(+) as to make the solution basic? Well with a pKa of 5.3 its close to not caring whether it holds onto a H at pH 7. That means there will be plenty of H's floating around. Hence acidic. (It is relative, you do have to compare the acid strengths).
So, lets assume its pyridine and not diethynemethyl amine nor cyclopentadienyl imine (I could possibly come up with a few others ...)
So your question is given the salt of a weak acid and a weak base how do you determine if the salt is acidic or basic?
pKa PyrH(+) = 5.25
pKa Chlorous Acid =1.96
In this situation it is clear that the salt will be acidic based on the Ka's.
The Ka or Kb is a measure of the tendency of the reaction HA +H2O → A(-) +H3O(+) or equivalently
B(+) + OH(-) ←BOH
There are several ways to calculate the pH of solutions but the way I look at it
given that chlorous acid is 'mostly' dissociated will the pyridine suck up so much of the H(+) as to make the solution basic? Well with a pKa of 5.3 its close to not caring whether it holds onto a H at pH 7. That means there will be plenty of H's floating around. Hence acidic. (It is relative, you do have to compare the acid strengths).