Section 1.1 Section 1.2 Section 1.3 - The Student Room

SECTION 13
Section 13.5
CH 3 C OH
CH 3 CH 2 OH
1 a methyl propanoate
b propyl ethanoate
c ethyl propanoate
d methyl methanoate
e methyl butanoate
2 a and b
Ester Alcohol Acid
ethyl methanoate ethanol methanoic acid
H C O CH 2 CH 3
H C OH
CH 3 CH 2 OH
O
O
3–methylbutyl ethanoate 3–methylbutanol ethanoic acid
CH 3 C O CH 2 CH 2 CHCH 3
CH 3 CHCH 2 CH 2 OH
O
CH 3
CH 3
O
ethyl 2–methylbutanoate ethanol 2–methylbutanoic acid
CH 3 CH 2 CH C O CH 2 CH 3
CH 3 CH 2 CH C OH
CH 3 O
CH 3 O
phenylmethyl ethanoate phenylmethanol ethanoic acid
O
CH 2 OH
CH 2 O C CH 3
CH 3 C OH
O
c They are structural isomers.
3 a
CH 3
CH
CH 3
CH 3 CH 2 CH 3 CH
O
O
OH
+
C
OH
CH 3
C CH 2
CH 3 H 2 O
O
+
b
HO
O
O
O
CH 2 CH 2 OH + 2CH 3 C OH CH 3 C O CH 2 CH 2 O C CH 3
+ 2H 2 O
4
O
O
O
O
O CH 2 CH 2 O C
C O
CH 2
CH 2
O
C
C
5 a The C–O bond next to the C=O in the ester is broken. c A hydrogen ion attaches itself to the oxygen of the
O
carbonyl group, and thus makes the carbon atom in
the group more susceptible to attack by a nucleophile
C CH 3
(eg water).
CH 3 CH 2 O
O
C CH 3 + H +
b The C=O bond is very polar with a d+ charge on the
carbon atom. Hydrolysis occurs by nucleophilic attack
CH 3 CH 2 O
on this carbon atom by a lone pair on the oxygen-18 of
a water molecule and the C–O bond break.
HO +
CH 3
CH 2
O
C
CH 3
A water molecule attacks the positive carbon atom, the
CH 3
–CH 2
–O – group is displaced and combines with H + to
form ethanol.
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