Qualitative Ka and Kb

[MedPR]

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I know that Kw=Ka*Kb for conjugates only, meaning that if the Kb for NH3 is 10^-5, the Ka is NOT 10^-9, but if the Ka for HCl is 10^-1, then the Kb for Cl- is 10^-13, etc.

However, I'm wondering if the following is accurate.

If A is a weaker base than B, A has a smaller Kb and a bigger pKb. Since A is a weaker base can we, qualitatively only, say that HA is a stronger acid than HB?

 

[chiddler]

I know that Kw=Ka*Kb for conjugates only, meaning that if the Kb for NH3 is 10^-5, the Ka is NOT 10^-9, but if the Ka for HCl is 10^-1, then the Kb for Cl- is 10^-13, etc.

However, I'm wondering if the following is accurate.

If A is a weaker base than B, A has a smaller Kb and a bigger pKb. Since A is a weaker base can we, qualitatively only, say that HA is a stronger acid than HB?

an easy way to see it.

flip it around again.

HA is a stronger acid than HB. Which do you expect to have a weaker/stronger base?

 

[MedPR]

an easy way to see it.

flip it around again.

HA is a stronger acid than HB. Which do you expect to have a weaker/stronger base?

HA stronger acid than HB. B stronger base than A!

Idk why this gives me so much trouble. I'm going to do the EK 1001 on this stuff tonight. I understand it, but I'm always really slow when it pops up on a passage or discrete. Need to get faster!