## 12.49

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

Katie 1E
Posts: 21
Joined: Fri Sep 29, 2017 7:04 am
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### 12.49

Where is the answer key getting the numbers used in the answer key for question 49? I understand that the pKb for morphine, 5.79 is from a table earlier in the chapter, but I couldn't find the values used for BrO-. Also, why was pKb used as opposed to Kb?

Krupa Prajapati
Posts: 50
Joined: Sat Jul 22, 2017 3:00 am

### Re: 12.49

Hi! From my understanding, either pKb or Kb are acceptable for understanding how strong a base is. In table 21.1 we se HBrO has pKa = 8.69. We know that since pKb = 14 - pKa, we find that pKb for BrO- is 5.31. Since the lower the Kb value the stronger the base, 5.31 < 5.79, we can conclude that BrO- is the stronger base.