The zwitter ion formed in an aqueous solution of glycine is

The correct answer is Option (1) → Neutral

A zwitterion (or dipolar ion) is a molecule that contains an equal number of positively charged functional groups and negatively charged functional groups.

Glycine ($\text{NH}_2\text{CH}_2\text{COOH}$) is the simplest amino acid. In an aqueous solution, it exists primarily as a zwitterion:

$\underbrace{\text{NH}_2\text{CH}_2\text{COOH}}_{\text{Glycine}} \overset{{\text{in water}}}{\longrightarrow} \underbrace{\text{H}_3\text{N}^+\text{CH}_2\text{COO}^-}_{\text{Zwitterion (Dipolar Ion)}}$

• The amino group ($\text{-NH}_2$) acts as a base and is protonated to form a positive group ($\text{-NH}_3^+$).
• The carboxyl group ($\text{-COOH}$) acts as an acid and is deprotonated to form a negative group ($\text{-COO}^-$).

Since the zwitterion form has one positive charge and one negative charge, the net charge on the molecule is zero ($\text{+1} + \text{-1} = 0$).

A molecule with a net zero charge is chemically neutral. This occurs at the isoelectric point ($\text{p}I$) of the amino acid.