pH
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Re: pH
It really depends on what information you are given, I feel like for most problems this is how I've been dealing with it...
1) convert pKa to Ka
Ka = 10^(-pKa)
2) write Ka concentration out and figure out [H+]
3) plug into pH = -log [H+]
1) convert pKa to Ka
Ka = 10^(-pKa)
2) write Ka concentration out and figure out [H+]
3) plug into pH = -log [H+]
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Re: pH
You would probably take the 10^-pka to convert it into Ka and then make a ICE table to find the concentration of H+ ions. After that, you would take the -log of the H+ concentration.
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Re: pH
Also be careful to check whether you’re given pKa or pKb and whether you want to find OH or H+ concentration
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Re: pH
Prasanna Padmanabham 4I wrote:It really depends on what information you are given, I feel like for most problems this is how I've been dealing with it...
1) convert pKa to Ka
Ka = 10^(-pKa)
2) write Ka concentration out and figure out [H+]
3) plug into pH = -log [H+]
I like this, clear and not too wordy :)
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Re: pH
If they give you the pKa, they would likely also have given the concentration of either [OH-] or [H3O+] or you would have to solve for them, and then you could use that value to do -log([H3O+]/[OH-]) and find the pH/pOH.
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Re: pH
You could convert pKa to Ka, then use Ka = 10^(-pKa). Use the Ka to find [H3O+]. Determine pH by this equation: pH = -log [H3O+].
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