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

Explanation

`alpha`-amino acids as we all know, are dipolar in nature `(overset(+)(N)H_(3)-CHR-COO^(-))` and have strong dipolar interactions. As a result, these are high melting solids. These are also involved in intermolecular hydrogen bonding with the molecules of water and are therefore, water soluble. On the contrary, the haloacidss RCH(X)COOH are not dipolar like `alpha`-amino acids. Moreover, only the carboxyl group of haloacids are involved in hydrogen bonding with the molecules of water and not the halogen atoms. These have therefore, comparatively less melting points and are also soluble in water to smaller extent.