Amino acids are classified as acidic, basic or neutral depending upon the relative number of amino and carboxyl groups in their molecule. Which of the following are acidic?
The answer is the option (ii) and (iv). In case of amino acids, the number of amino and carboxyl groups in their structure determines their acidic nature, more carboxyl groups increase their acidic nature. From the compounds given above, only (ii) and (iv) have only one amino group and two carboxyl groups. Therefore option (ii) and (iv) are the answers.