For glycine ( $p K_{a 1} = 2.34$ , $p K_{a 2} = 9.60$ ), the average net charge of the species present at pH 2.34 is, to the nearest 0.1,

A0.0
B+1.0
C-0.5
D+0.5

Answer: D

At pH = pKa1 the COOH group is half ionised: half the molecules are the cation (+1), half the zwitterion (0), giving +0.5. The NH3+ group (pKa 9.60) remains fully protonated and is already counted in the +1 cation.

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For glycine (pKa1​=2.34, pKa2​=9.60), the average net charge of the species present at pH 2.34 is, to the nearest 0.1,

Answer: D

More questions on Amino acids: zwitterions, isoelectric point

For glycine ( $p K_{a 1} = 2.34$ , $p K_{a 2} = 9.60$ ), the average net charge of the species present at pH 2.34 is, to the nearest 0.1,