- Axit: 

(1) $CH_3-CH_2-CH_2-CH_2-COOH$: axit pentanoic 

(2) $CH_3-CH(COOH)-CH_2-CH_3$: axit 2-metylbutanoic 

(3) $CH_3-CH(CH_3)-CH_2-COOH$: axit 3-metylbutanoic 

(4) $CH_3-C(COOH)(CH_3)-CH_3$: axit 2,2-đimetylpropanoic 

- Este:

$HCOOCH_2-CH_2-CH_2-CH_3$: butyl fomat 

$HCOOCH_2-CH(CH_3)-CH_3$: isobutyl fomat 

$HCOOCH(CH_3)-CH_2-CH_3$: sec-butyl fomat 

$HCOOC(CH_3)(CH_3)-CH_3$: tert-butyl fomat 

$CH_3COOCH_2-CH_2-CH_3$: propyl axetat 

$CH_3COOCH(CH_3)-CH_3$: isopropyl axetat 

$CH_3-CH_2COOCH_2-CH_3$: etyl propionat 

$CH_3-CH_2-CH_2-COOCH_3$: metyl butirat 

$CH_3-CH(CH_3)-COOCH_3$: metyl isobutirat

Đáp án:

CTCT của axit cacboxylic: $C5H10O2$

$CH3CH2CH2CH2COOH$: Axit pentanoic

$CH3CH2CH(CH3)COOH$: Axit 2 - metylbutanoic

$CH3CH(CH3)CH2COOH$: Axit 3 - metylbutanoic

$(CH3)3CCOOH$: Axit 2,2 - đimetylpropanoic