(i) Write the product obtained when D-glucose reacts with H₂N - OH.
(ii) Amino acids show amphoteric behaviour. Why?
(iii) Why cannot vitamin C be stored in our body?

(i) When D-glucose reacts with NH₂OH, an aldoxime is formed.

(ii) In aqueous solutions, the carboxyl groups of amino acids lose a proton. Amino groups of amino acids, on the other hand, accept a proton, giving rise to a dipolar ion known as zwitter ion.

This is neutral, but contains both positive and negative charges. In the zwitter ionic form, amino acids show amphoteric behaviour as they react with both acids and bases.

(iii) Vitamin C is water soluble and is readily excreted in urine. Hence, it cannot be stored in our body.