## 12.57

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

Humza_Khan_2J
Posts: 56
Joined: Thu Jul 13, 2017 3:00 am

### 12.57

How do we know the answer in 12.57 will only be one sig fig? I used two and it gave a pretty different answer (.10 versus the book's .09). Thanks!

Rachel Lu_dis1H
Posts: 66
Joined: Fri Sep 29, 2017 7:06 am
Been upvoted: 1 time

### Re: 12.57

Since the sigfigs in the question is all 2 or 4, i assume that your answer would be correct. I'm assuming it's just an error in the solution manual.

Magdalena Palavecino 1A
Posts: 54
Joined: Fri Sep 29, 2017 7:04 am

### Re: 12.57

Can someone please explain how to do this problem? I've been trying to do it for over thirty minutes now.

Jingyi Li 2C
Posts: 56
Joined: Fri Sep 29, 2017 7:06 am

### Re: 12.57

For part a, since you are given the pH value of HClO2, you can first calculate the molarity of H3O+. Then, you get the molarity of its conjugate base as it is the same as the hydronium ions. The question you probably have when calculating Ka is the equilibrium concentration of HClO2, which you get by subtract the amount deprotonated from the original molarity. From here, you can get pKa. And part b is the same process of part 1.