## pKa vs. pH

Lumbini Chandrasekera 1B
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Joined: Fri Sep 28, 2018 12:18 am

### pKa vs. pH

Why isn't pKa the same as pH?

katherinemurk 2B
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### Re: pKa vs. pH

pKa is a the -log of the acid dissociation constant, it is a measure of acid strength. pH is a measure of the concentration of H+ ions.

Karan Thaker 2L
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Joined: Fri Sep 28, 2018 12:26 am

### Re: pKa vs. pH

They're both logarithmic expression of completely different things. pKa is a logarithmic expression of Ka values while pH is a logarithmic expression of hydrogen ion concentration.

Kyither Min 2K
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Joined: Wed Oct 03, 2018 12:15 am

### Re: pKa vs. pH

pKa stands for -log of Ka and pH stands for -log of Hydronium ions. Consider the p as a function rather than a symbol. All the p does is mathematically change the value, similar to a negative sign or derivative. Ka is the dissociation of an acid or the equilibrium constant for the acid whereas H is just the concentration of H3O+. The two measure different things.

Anand Narayan 1G
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### Re: pKa vs. pH

This is because pKa is a the -log of Ka, the acid dissociation constant, it is a measure of acid strength. pH, on the other hand is a measure of the concentration of H+ ions.

405021651
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### Re: pKa vs. pH

The pKa is the -log(Ka)

505211599
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### Re: pKa vs. pH

The pKa is the -log(Ka) and pH is -log(H+)

abbydouglas1K
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### Re: pKa vs. pH

pKa and pH measure different quantities. pKa measurers acid strength and pH measures H+ concentration, which are similar but Ka is used to find pKa as opposed to a molar cpncenztrartion of H+ ions in a solution.

JacobHershenhouse3G
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### Re: pKa vs. pH

Don't let yourself be confused by similar notation because they mean dramatically different things. p just means -log, so in this case you are taking the negative log of a constant and of a concentration, therefore it is evident that the interpretation of these numbers mean different things. Both values gives you insight on how strong or weak an acid or base. Yet, taking the pka of an acid base reaction gives you perspective in relation to pKw=1e-14 and pH does so on a scale of 0 to 14.

Zubair Ahmed 1L
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Joined: Fri Sep 28, 2018 12:16 am

### Re: pKa vs. pH

The pKa and the pH represent two different things. The pKa is the -log(Ka) and can be used to determine the strength of an acid. On the other hand, the pH is the -log(H+) concentration.

Nina Do 4L
Posts: 61
Joined: Fri Sep 28, 2018 12:27 am

### Re: pKa vs. pH

pKa is the -log of the Ka value and Ka*kB=1x10^-4 so you can find out the value of Ka/pka if you're given the value of Kb.

pH is the -log of H+ or H3O+.

The 'p' is -log-ing different values, therefore they are different. Hope this helps.

Ricardo Martin 1J
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Joined: Fri Sep 28, 2018 12:15 am

### Re: pKa vs. pH

pH is the concentration f hydrogen ions in the solution.

Ashley P 4I
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Joined: Wed Nov 15, 2017 3:04 am

### Re: pKa vs. pH

pKa= -log of Ka
pH stand= -log of Hydronium ions.

Nghi Nguyen 2L
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Joined: Fri Sep 28, 2018 12:18 am

### Re: pKa vs. pH

pKa = -log(Ka)
pH = -log(H+)

Roberto Gonzalez 1L
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Joined: Fri Sep 28, 2018 12:17 am

### Re: pKa vs. pH

pH can be solved for by taking the -log of the concentration of hydronium ions, and therefore quantitatively describes the acidity or basicity of a solution. pKa is found taking the -log of the ionization constant of an acid, and can therefore be used to understand the strength of an acid.

Anita Wong 1H
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Joined: Fri Sep 28, 2018 12:27 am
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### Re: pKa vs. pH

pka is in reference to ka whereas ph is in reference to H+

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