Question
How do you explain the amphoteric behaviour of amino acids?
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Answer
Due to the presence of both acidic $(- COOH )$ and basic $\left(- NH _2\right)$ groups in the same molecule in amino acids, they behave like salts.
In aqueous solution of amino acids, the carboxyl group can donate (lose) a proton and amino group can accept a proton due to which a dipolar ion is formed known as Zwitter ion or inner salt. This is neutral but contains both positive and negative charge.
In zwitter ionic form, amino acids exhibit amphoteric behaviour because they react both with acids and bases.
In aqueous solution of amino acids, the carboxyl group can donate (lose) a proton and amino group can accept a proton due to which a dipolar ion is formed known as Zwitter ion or inner salt. This is neutral but contains both positive and negative charge.
In zwitter ionic form, amino acids exhibit amphoteric behaviour because they react both with acids and bases.
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