Carboxylic acids

Question 1

What is the prefix for carboxylic acids?

Answer 1

anoic acid

Question 2

What is the prefix for a compound with 2 carboxylic acid func groups?

Answer 2

dioc acid

Question 3

What state are carboxylic acids at room temp?

Answer 3

liquid

Question 4

Which has a higher BP an alcohol or a carboxylic acid? and why?

Answer 4

higher in a carboxylic acid = carboxylic acid is more polar than alcohol so permenant d-d forces
and carboxylics have a structure which allows them to form more H bonds

Question 5

Are carboxylic acids soluble in water?

Answer 5

yes = they form H bonds

Question 6

What affects the solubility of carboxylic acids in water?

Answer 6

the longer the hydrocarbon chain, solubility decreases = it is non-polar
this can outweigh the polar OH group

Question 7

Are carboxylic acids strong or weak acids?

Answer 7

weak = only slightly soluble in aq solution

Question 8

What is a derivative?

Answer 8

a compound in which the functional group of a compound is converted into something different

Question 9

What are all the derivatives of carboxylic acids?

Answer 9

esthers
acyl chlorides
acid anhydrides
amides

Question 10

What is the functional group of esthers?

Answer 10

RCOOR

Question 11

What is the name ending for esthers?

Answer 11

anoate

Question 12

Do esthers have a lower or higher MP and BP than carboxylic acids?

Answer 12

lower
esthers only form permanent d-d and induced
carboxylic acids form H bonds

Question 13

How can you make an esther from a carboxylic acid? What is the process called?

Answer 13

Esterification of a carboxylic acid with an alcohol
adding an alcohol to a carboxylic acid
condensation reaction

Question 14

What is the general reaction of esterification of a carboxylic acid with an alcohol?

Answer 14

carboxylic acid + alcohol —> ester + water

Question 15

What type of reaction is esterification?

Answer 15

condensation = water molecule is removed

Question 16

What are the conditions for esterification?

Answer 16

conc H2SO4 and heat
reflux

Question 17

What are acid anhydrides?

Answer 17

compunds formed by the dehydration of carboxylic acids

Question 18

What is the general formula of acid anhydrides?

Answer 18

RCOOCOR

Carbon double bonded to an O with an R group
bonded to an O that is bonded to another Carbon double bonded to an O with an R group

Question 19

How do you name acid anhydrides?

Answer 19

anoic anhydride

Question 20

How is an acid anhydride formed?

Answer 20

formed from 2 carboxylic acids by the elimination of water

Question 21

How do you form an ester from an acid anhydride?

Answer 21

anhydride and alcohol makes an ester and carboxylic acid

Question 22

what is the equation reacting an acid anhydride with an alcohol?

Answer 22

anhydride + alcohol —> ester + carboxylic acid

Question 23

What is the condition for reacting an acid anhydride with an alcohol?

Answer 23

gentle heat
no catalyst

Question 24

What are the advantages of producing esters from acid anhydrides rather than carboxylic acids?

Answer 24

milder conditions = stong acid catalyst needed for carboxylic reaction which might cause further reaction of other functional groups

reaction with acid anhydrides is irreversible = easier to get a higher yield of ester using anhydride

Question 25

What is a hydrolysis reaction?

Answer 25

a reaction which a compound is broken down by addition of a water molecule

Question 26

What reacts with an ester in base catalysed hydrolysis?

Answer 26

NaOH - for OH-

Question 27

What does base catalysed hydrolysis form?

Answer 27

alcohol and the salt of the carboxylic acid

Question 28

What are the conditions of base hydrolysis of an ester?

Answer 28

refulx with aq NaOH

Question 29

Why is base catalysed hydrolysis better than hydrolysing a ester with water?

Answer 29

irreversible reaction so it gives higher yields

Question 30

How do you convert the carboxylic salt into its carboxylic acid?

Answer 30

neutralise with aq acid distill off the carboxylic acid

Question 31

What are the 2 types of hydrolysis?

Answer 31

acid catalysed base catalysed

Question 32

What are the products of base catalysed hydrolysis?

Answer 32

salt and alcohol

Question 33

Why does acid catalysed hydrolysis produce a lower yield?

Answer 33

it is reversible

Question 34

What are the conditions for acid catalysed hydrolysis?

Answer 34

reflux with aq HCl

Question 35

What are the uses of esters?

Answer 35

simple (low mr) esters are volatile and have pleasant, fruity smells which are used in flavourings and perfumes

Question 36

What are acyl chlorides?

Answer 36

carboxylic derivative which the OH group is replaced with a Cl

Question 37

How do you name acyl chlorides?

Answer 37

oyl chloride

Question 38

How do you make acyl chlorides?

Answer 38

use the parent carboxylic acid with SOCl2

Question 39

What is SOCL2 called?

Answer 39

thionyl chloride

Question 40

Why are acyl chlorides used in synthesis?

Answer 40

they are very reactive because the chlorine readily leaves as Cl- to be replaced by other groups

Question 41

What are the 2 reactions of acyl chlorides you need to know?

Answer 41

Friedel-Crafts acylation - halogen carrier and aromatic compound adding an alcohol to form an ester

Question 42

How can esters be made from acyl chlorides?

Answer 42

add an alcohol to form ester and HCl

Question 43

What are the advanatges of making on ester from acyl chloride than estrifying a carboxylic acid?

Answer 43

reaction with acyl chlorides happens more rapidly no catalyst needed and no heat high yield used to esterify phenols which will not directly react with carboxylic acids to form phenol esters6+

Question 44

How can acyl chlorides be converted into carboxylic acids?

Answer 44

add water to acyl chloride to produce carboxylic and HCl

Question 45

How can acyl chlorides form amides?

Answer 45

acyl chlorides react with ammonia to make amines to make amides

Question 46

How is a carboxylic acid formed from a base hydrolysis of an ester?

Answer 46

add H+ to the salt

Question 47

How do you remove a carboxylic acid from a solution?

Answer 47

if its a solid = it will precipitate out if its oil = will form a layer of oil which needs to be separated using a separating funnel if it's a liquid = distillation

Question 48

What are the conditions for forming an ester from a RCOOH and ROH?

Answer 48

heat under reflux acid catalyst

Question 49

How do you form a RCOOH from a nitrile? (conditions)

Answer 49

HCl, H2O and heat