Difference between pH and pKa?

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Ryan Fang 1D
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Joined: Sat Jul 22, 2017 3:00 am

Difference between pH and pKa?

Postby Ryan Fang 1D » Mon Dec 04, 2017 12:36 pm

Is there a difference between these two values or are they the same?

Chem_Mod
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Re: Difference between pH and pKa?

Postby Chem_Mod » Mon Dec 04, 2017 2:04 pm

They are different. The pH is that of the solution whereas the pKa is the negative log of the acid equilibrium constant for a particular acid (-log(Ka)). This is used as a measure of acid strength for that acid.

Leanne Wong 1H
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Re: Difference between pH and pKa?

Postby Leanne Wong 1H » Tue Dec 05, 2017 4:42 pm

pH is the measure of the concentration of hydrogen ions whereas pKa the acid dissociation constant and is able to predict what a molecule would do at specific pH.

AnuPanneerselvam1H
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Re: Difference between pH and pKa?

Postby AnuPanneerselvam1H » Thu Dec 07, 2017 2:02 am

pKa and pH are different. Ka is the equilibrium constant for a reaction that involves an acid. pKa = -log(Ka). pH is a measure of how strong the acid is (how much it disassociates. pH = -log[H+]

Navleen Bajwa 3A
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Re: Difference between pH and pKa?

Postby Navleen Bajwa 3A » Fri Dec 08, 2017 12:18 am

pH is the hydronium ion concentration of the solution. The pH is the negative logarithm of the hydronium ion activity. pKa is the negative base -10 logarithm of the acid dissociation constant of a solution. The lower the pKa value, the stronger the acid.


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