+) 4 đồng phân axit cacboxylic:
1. CH3CH2CH2CH2COOH: axit pentanoic
2. CH3CH2CH(CH3)COOH: axit 2-metylbutanoic
3. CH3CH(CH3)CH2COOH: axit 3-metylbutanoic
4. (CH3)3CCOOH: axit 2,2-đimetylpropanoic
+) 9 đồng phân este:
1. CH3CH2CH2COOCH3: metyl pentanoat
2. CH3CH(CH3)COOCH3: metyl 2-metylpropanoat
3. CH3CH2COOCH2CH3: etyl propionat
4. CH3COOCH2CH2CH3: propyl axetat
5. CH3COOCH(CH3)2: isopropyl axeta
6. HCOOCH2CH2CH2CH3: butyl fomat
7. HCOOCH(CH3)CH2CH3: sec-butyl fomat
8. HCOOCH2CH(CH3)2: iso-butyl fomat
9. HCOOC(CH3)3: tert-butyl fomat
