Assertion (A): Amino acids have much higher melting points than amines or carboxylic acids of comparable molar mass. Reason (R): In the solid state amino acids exist as zwitterions held together by strong electrostatic attractions.

ABoth A and R are true, but R is not the correct explanation of A
BA is true but R is false
CA is false but R is true
DBoth A and R are true, and R is the correct explanation of A

Answer: D

The dipolar ionic lattice (-NH3+ and -COO-) needs much more energy to break than the weaker H-bonds or dipole forces of neutral amines and acids. A is true and R is the correct reason.

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