## Textbook Problem 6C.13

Acidity $K_{a}$
Basicity $K_{b}$
The Conjugate Seesaw $K_{a}\times K_{b}=K_{w}$

Mahnoor_Wani_1I
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### Textbook Problem 6C.13

6C.13 Arrange the following bases in order of increasing strength on the basis of the pKa values of their conjugate acids, which are given in parentheses: (a) ammonia (9.26); (b) methylamine (10.56); (c) ethylamine (10.81); (d) aniline (4.63; see Exercise 6C.12).
Is there a simple pattern of strengths?

I understand how to do the first part of the problem: putting in order of strength of basis (high aka value = strong conjugate base). However, I can't seem to find any pattern from the diagrams given in exercise 6c.12. Could someone explain to me what the pattern is?

Marisa Gaitan 2D
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### Re: Textbook Problem 6C.13

I was also confused on this. I couldn't find any pattern, but the solutions manual noted that generally, arylamines < ammonia < alkylamines and that methyl < ethyl < etc. I'm not sure if we need to specifically know these patterns, but it gave me a better sense of what question was asking for in the first place. Hope this helps.

Mahnoor_Wani_1I
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### Re: Textbook Problem 6C.13

Thank you! That make sense