Sort the following formulas or structures as carboxylic acids, esters, or amides. Sort the following formulas or structures as carboxylic acids, esters, or amides. Carboxylic acid Ester Amide Solution compounds with (i) -COOH group are acids CH3COOH, PhCOOH, RCOOH (ii) -CONH2 amide CH3CH2CONH2, RCONH2 (iii) -O(C=O)-R esters RCOOR\', CH3CH2O(C=O)CH(CH3)CH2CH3.