How to calculate % ionization of amino acids?

[Hades]

What percentage of side chain group of histidine that is in basic form at 6.5 have if the pKa for the side chain is 6.0.

 

how is this done?

[MattC]

Sounds like an O-Chem homework question. Here's a hint: What does pka mean? If you can make the 6.0 equal to something, say some function of certain concentrations, and you can do the similar things with other relevant parts of the question ... and if you can put that together ... you can get a concentration.