The increasing order of pKa of the following amino acids in aqueous solution is Gly, Asp, Lys, Arg

Question

The increasing order of pKa of the following amino acids in aqueous solution is Gly, Asp, Lys, Arg (A) Asp < Gly < Arg < Lys (B) Arg < Lys < Gly < Asp (C) Gly < Asp < Arg < Lys (D) Asp < Gly < Lys <Arg

Tardigrade Admin · Accepted Answer

Order of acidic strength Solution

Ka propto number of âCOOH groups propto (1/n o . o f â N H2 g r o u p s) So, pKa propto (1/Ka) Asp < Gly < Lys < Arg

Q. The increasing order of $p K_{a}$ of the following amino acids in aqueous solution is Gly, Asp, Lys, Arg

Asp < Gly < Arg < Lys

Arg < Lys < Gly < Asp

Gly < Asp < Arg < Lys

Asp < Gly < Lys

8%

Order of acidic strength

$K_{a} \propto$ number of —COOH groups

$\propto \frac{1}{n o . o f — N H _{2} g ro u p s}$

So, $p K_{a} \propto \frac{1}{K _{a}}$
$A s p < Gl y < L ys < A r g$

Q. The increasing order of pKa​ of the following amino acids in aqueous solution is Gly, Asp, Lys, Arg