pKa to Kb
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pKa to Kb
im a little confused on how to convert pKa to Kb? I think theres multiple ways, but what's the easiest way to do it?
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Re: pKa to Kb
Another way to do it is to turn the pKa into Ka first. Once you turn it into ka you can use the kw (water constant) to find the kb. Set the equation to be kb=kw/ka.
Re: pKa to Kb
You can go from pka to ka by taking 10 to the power of negative pka and when you found ka you can easily divide 10 to the power of negative 14 by ka to get kb
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Re: pKa to Kb
So the simplest way would be to find Pkb using the equation 14=pka+pkb. Once you find your pkb, you can use it to find kb using 10^-pkb.
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Re: pKa to Kb
What makes logical sense for me is to think, pka=-log(Ka), therefore Ka=10^-pka. Then we know Kw= Ka x Kb and so you should rearrange the equation so that Kw/Ka=Kb and now you have your Kb value! Make sure you take it slow and pay close attention.
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Re: pKa to Kb
Nawal Dandachi 1G wrote:pKa + pKb = 14, so solve for pKb. After finding pKb, use pKb = -log(kb) to find Kb
I thought by doing the -log, you would get pKb? Wouldn't you need to 10^pKb to get Kb? Or did I switch it?
Re: pKa to Kb
Also, I'm forgetting the concentration equation for pKb, can someone help me with that? Thanks!
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