The melting points and solubility in water of amino acids are generally higher than that of the corresponding halo acids. Explain.

Explanation

The amino acids exist as Zwitter ions, `H_(3)N^(+) - CHR - COO-`. Due to this dipolar salt like character, they have stron dipole-dipole attractions. Therefore, their melting points are higher than corresponding haloacids which do not have salt like character.
Due to salt like character, amino acids intereact strongly with water. As a result, their solubility in water is higher than corresponding haloacids which do not have salt like character.