Question

name a isomer of ch3cooh

Answer 1

i think the question is wrong because by 2 carbon atoms you cannot make isomers

Answer 2

Isomers are the organic compounds having same molecular formula but different molecular structure.

Acetic Acid-- CH3OOH  and methyl Formate are functional isomers.

They have same molecular formula : C2H4O2
Acetic acid --- Belongs to carboxylic groups with -COOH group.        
        O         
        II
H3C-C-OH

Methyl Formate is an ester with group ---COOCH3 group:     
     O    
     II
H- C-OCH3