Question

Assertion : Alpha $(\alpha)$ -amino acids exist as internal salt in solution as they have amino and carboxylic acid groups in near vicinity.
Reason: $H ^{+}$ ion given by carboxylic group (-COOH) is captured by amino group $(-NH _{2})$ having lone pair of electrons.

• A. If both assertion and reason are true and reason is the correct explanation of assertion
• B. If both assertion and reason are true but reason is not the correct explanation of assertion
• C. If assertion is true but reason is false
• D. If both assertion and reason are false

Answer 1

Answer: (A)

$NH_{2}-CH_{2}-COOH$ is a typical $\alpha$ amino acid. In solution it exists as, internal salt or Z witter ion,

$\left(^{+}NH_{3}-CH_{2}-COO^{-}\right)$

because the proton ($H^+$ ) of COOH group is captured by $-NH^2$ group as $NH^2$ has a lone pair of electrons on N atom.