## 6D.7

Emily Chirila 2E
Posts: 112
Joined: Sat Jul 20, 2019 12:16 am

### 6D.7

The problem:
Find the initial concentration of the weak acid or base in each of the following aqueous solutions: (a) a solution of HCLO with pH=4.60 (b) a solution of hydrazine, NH2NH2, with pH=10.20

Is there a way to solve this without Ka values? I looked up the Ka values and used them to solve and my answer was correct, but I'm wondering if that information would be provided to us on our exam... Should I be able to do this problem without being provided the Ka values?

Vincent Leong 2B
Posts: 207
Joined: Fri Aug 09, 2019 12:15 am

### Re: 6D.7

You have to know the Ka value of both compounds to find the initial concentration. Given pH, you can only determine the concentration of H3O+, OH-, pOH, and probably other products but never the initial concentration by given just the solutions pH.

KBELTRAMI_1E
Posts: 108
Joined: Sat Jul 20, 2019 12:17 am

### Re: 6D.7

Can you solve for the Ka using pH? Like pKa is related to pH enough? Not sure