# Ionization Problem

#### Fragment

1. The problem statement, all variables and given/known data

A 0.085 M aqueous solution of a weak base is known to be 1.6 percent ionized. Calculate the pH of the solution.

2. Relevant equations

%Ionization= ([OH-] derived from base/ initial [base]) x 100%
pOH=-log[OH-}

3. The attempt at a solution

%Ionization= ([OH-] derived from base/ initial [base]) x 100%
1.6%=[OH]/0.085M
[OH]=0.136M

pOH=-log[OH-]
pOH=-log(o.136M)
pOH=0.866
pH+pOH=14, 14-0.866=13.134...

I normally do these without a problem, so I'm assuming it's a stupid mistake. The problem clearly says weak base...Where am I going wrong?

Regards,
Fragment

#### Borek

Mentor
%Ionization= ([OH-] derived from base/ initial [base]) x 100%
1.6%=[OH]/0.085M
[OH]=0.136M
Check your math. You are right - it is a stupid mistake. Not that uncommon though.

#### Fragment

Hahaha, I even double checked it the other night. How lame. Thanks

### The Physics Forums Way

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving