December 04, 2020, 09:58:38 PM
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Topic: Ionic strength question  (Read 10135 times)

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Offline SpellForce

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Re: Ionic strength question
« Reply #15 on: June 27, 2014, 07:35:10 AM »
And what is the best source to look for pKa values? I found somewhere that pKa2 of phosphoric acid is 7.2, and somewhere its 6.8...

Offline SpellForce

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Re: Ionic strength question
« Reply #16 on: June 27, 2014, 10:50:01 AM »
Never mind, I found a way to calculate it :D

Offline Borek

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Re: Ionic strength question
« Reply #17 on: June 27, 2014, 12:33:27 PM »
And what is the best source to look for pKa values? I found somewhere that pKa2 of phosphoric acid is 7.2, and somewhere its 6.8...

Most likely these are values listed form different ionic strengths. For IS=0 it should be 7.199 if memory serves me well.
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Offline Babcock_Hall

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Re: Ionic strength question
« Reply #18 on: September 16, 2016, 05:49:54 PM »
Buffer Solutions: The Basics, by Beynon and Easterly has the best intermediate-level discussion of the effect of ionic strength on pKa that I have found.  They present a formula for estimating the shift in pKa with ionic strength.

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