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Can someone please explain or share a link about the relation between PH and PKa of substances like amino acids and how amino acids have different charges at different PH levels. I really don't get it. :toosad:
 

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Pka of a substance is the PH at which half of it is charged and half uncharged.
water has a pka of 7. Anything below it is acidic and above it is alkaline.
if an acidic amino acid has a pka of 3; below 3, it will be acidic for that amino acid and in a PH of 2 it will be uncharged. An acid in acidic medium is uncharged. Mnemonic for that is a male doesn't get charged in the presence of the males; it has to be in the opposite medium. Above a PH of 3 it will be alkaline for that amino acid and it will be charged. Do the vice versa for basic amino acids until ur head starts spinning.
 
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