relationship between Ka, Kb, and its ability to donate

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Hai-Lin Yeh 1J
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relationship between Ka, Kb, and its ability to donate

Postby Hai-Lin Yeh 1J » Wed Jan 16, 2019 4:13 pm

Is this correct:
The smaller the value of Ka, the weaker the ability of the acid to donate a proton, but the greater the value of pKa. This also means the acid is very weak. Similarly, the smaller the value of Kb, the weaker the ability of the base to accept a proton, but the greater value of pKb. This means the base is also very weak?

Rachel-Weisz3C
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Joined: Fri Sep 28, 2018 12:23 am

Re: relationship between Ka, Kb, and its ability to donate

Postby Rachel-Weisz3C » Wed Jan 16, 2019 4:23 pm

That sounds right! Also, as Ka increases, Kb decreases and vice versa, since Ka x Kb = Kw.

Riya Shah 4H
Posts: 65
Joined: Wed May 02, 2018 3:00 am

Re: relationship between Ka, Kb, and its ability to donate

Postby Riya Shah 4H » Thu Jan 17, 2019 4:08 pm

So if you are given a pKa value of a conjugate acid which is large, does that mean the base is strong?

Max Hayama 4K
Posts: 63
Joined: Fri Sep 28, 2018 12:16 am

Re: relationship between Ka, Kb, and its ability to donate

Postby Max Hayama 4K » Thu Jan 17, 2019 4:12 pm

I believe this is correct! If the conjugate acid has a high pKa, the Ka value is small, meaning the ability to donate a proton is not strong. Therefore the ability for the conjugate acid to form the base is also small, meaning the base is strong.


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