WM - Carboxylic Acids and Esters

Question 1

what is the functional group of a carboxylic acid?

Answer 1

COOH

Question 2

what are the 2 derivatives of a COOH?

Answer 2

ester
acid anhydride

Question 3

what is the suffix for an acid anhydride?

Answer 3

-oic anhydride

Question 4

describe esterification:

Answer 4

alcohol + COOH —> ester + water
with strong sulphuric acid catalyst

Question 5

characteristics of esterification:

Answer 5

they reaction is reversible and quite slow and requires HUR
low yields of desired product (50%) is achieved
an acid catalyst is needed

Question 6

why is esterification of an acid anhydride better then COOH?

Answer 6

the reaction isn reversible but higher yield is achieved as anhydride is more reactive then COOH
> alcohol reagent
> room temp

Question 7

how can esters be hydrolysed?

Answer 7

by either heating with an acid or with sodium hydroxide

Question 8

hydrolysis of ester in acid conditions:

Answer 8

HCl is required and HUR
it is the reverse reaction of ester formation (carboxylic acid and alcohol are formed)
the reaction is reversible
only gives low yield

Question 9

hydrolysis of an ester with dilute sodium hydroxide as reagent:

Answer 9

dilute sodium hydroxide is required and HUR
the reaction is not reversible as carboxylic acid salt product is COO- which weakens nucleophiles (alcohol) during reaction
the reaction goes to completion

Question 10

what are the acidic properties of a COOH?

Answer 10

they’re only weak acids in water so only cause a slight dissociation