The acidic dissociation constants for valine are (for the carboxyl group) and (for the ammonium grou — Biomolecules Chemistry Question

💡 Solution & Explanation

For an amino acid with an uncharged (neutral) non-ionizable side chain like valine, the isoelectric point ($pI$) is merely the arithmetic mean of the two core $pKa$ values surrounding the zwitterion phase. $pI = \frac{pKa_1 + pKa_2}{2} = \frac{2.30 + 9.70}{2} = \frac{12.00}{2} = 6.00$.