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### pH and pOH

Posted: Sun Jan 20, 2019 8:44 pm
How do you know which one to solve for? For instance on 6B.5.

### Re: pH and pOH

Posted: Sun Jan 20, 2019 9:03 pm
What does the problem say? I think generally it tells you which to solve for.

### Re: pH and pOH

Posted: Sun Jan 20, 2019 9:06 pm
dont know what the question says but I think for most questions it specifies to solve for either one or the other or both

### Re: pH and pOH

Posted: Sun Jan 20, 2019 9:25 pm
I don't know what the problem says but usually, it will tell you what to solve for in the problem. Given the reaction, you will know what you have to solve for. For instance if it NH3 + H20 -> NH4+ + OH- you would solve for Kb and pOH and if it was HCl + H20 -> Cl- + H30+.

### Re: pH and pOH

Posted: Sun Jan 27, 2019 10:03 pm
If it doesn't tell you explicitly, just go off of what's present in the equation. Which do you end up with in the products - H3O+ or OH-? If it's OH-, then pOH. If it's H3O+, then pH. And of course you can always calculate one once you have the other using the equation pH + pOH = 14.

### Re: pH and pOH

Posted: Sun Jan 27, 2019 10:11 pm
Usually the question will ask you to solve for one or the other.

### Re: pH and pOH

Posted: Mon Jan 28, 2019 12:54 am
The question will tell whether to solve for ph or pOH.

### Re: pH and pOH

Posted: Mon Jan 28, 2019 1:04 am
The question will ask you to solve for pH or pOH, and the problem will also give you sufficient information to be able to solve for this.

### Re: pH and pOH

Posted: Mon Jan 28, 2019 10:12 am
The probable will typically tell you whether to solve for pH or pOH.

### Re: pH and pOH

Posted: Mon Jan 28, 2019 8:50 pm
Also, when your chemical reaction includes H30+, you are finding the pH, and when it includes OH-, you are finding the pOH. Make sure to use the equation pH+pOH=14 if you are trying to convert between the two.

### Re: pH and pOH

Posted: Mon Jan 28, 2019 9:07 pm
pOH- base
pH-acid

then you can use the pOH+pH=14 to solve for the other one

### Re: pH and pOH

Posted: Wed Jan 30, 2019 10:36 pm
The question will tell you which to solve for.

### Re: pH and pOH

Posted: Wed Jan 30, 2019 10:40 pm
Typically if you are given a base, you solve for pOH, but if you are asked to find the pH, then you must convert from pOH to pH by using this formula: -14.00 = pOH + pH. Or 14.00 - pOH = pH

### Re: pH and pOH

Posted: Sun Feb 10, 2019 3:38 pm
Usually the problem you are solving will tell you which one to solve for. In some occasions you may have to solve for both for the same problem.

### Re: pH and pOH

Posted: Sun Feb 10, 2019 10:30 pm
Often times if they don't say it outright, you can infer through whether they are referring to the concentrations of acids or bases in a solution.

### Re: pH and pOH

Posted: Mon Feb 11, 2019 11:11 am
If it doesnâ€™t say specifically look at the products as OH would be pOh and H3O would be pH, sometimes it will tell you specifically

### Re: pH and pOH

Posted: Tue Feb 12, 2019 1:08 pm
It is always best to go with what is given, if OH is formed, then solve for pOH and then 14-pOH to find pH. If H+ is a product of the disassociation, then solve for pH and then use 14-pH if they are asking for pOH?

### Re: pH and pOH

Posted: Sat Feb 16, 2019 9:45 pm
The problem should specify, but if not it is usually safe to assume you should calculate for what is given, ie if the reaction forms H+ ions you should solve for pH and if OH- ions are formed solve for pOH.

### Re: pH and pOH

Posted: Sat Mar 16, 2019 12:56 pm
it will ask you specifically but usually it is pH