## 12.67 Calculating pH from Molarity and Formula

HoganFenster2E
Posts: 23
Joined: Fri Sep 25, 2015 3:00 am

### 12.67 Calculating pH from Molarity and Formula

For question 12.67 in the homework, when you are given the molarity and molecular formula, how are we supposed to go about ranking the pH. I was thinking the ice box however the solutions manual does not do this. It seems like it does it a much easier way. Can you rank the pH's just by looking at the molarities and formula?
Given:
1x10^-5 M HCL
0.20 M CH3NH3Cl
0.20 M CH3COOH
0.20 M C6H5NH2

Chloe 3D
Posts: 21
Joined: Fri Sep 25, 2015 3:00 am

### Re: 12.67 Calculating pH from Molarity and Formula

I think you use the molecular formula to determine whether each compound is an acid or a base. From there, you can take the negative log of the molarities to find the pH (if the compound is an acid) or the pOH (if the compound is a base). Once you have the pOH, subtract this value from 14.00 to find the pH of the base.

Return to “Calculating pH or pOH for Strong & Weak Acids & Bases”

### Who is online

Users browsing this forum: No registered users and 1 guest