Reactions Of Carboxylic Acids

Question 1

Reactions of carboxylic acids

Answer 1

Neutralisation to form a salt
Reduction to primary alcohol
React with PCl5 to form an acyl chloride

Question 2

Neutralisation of carboxylic acid with a hydroxide

Answer 2

Forms salt and water: removes H+ ion on OH and replaces with metal
H+ ion reacts with OH- ion in base to form water

Question 3

Reduction of carboxylic acids

Answer 3

Back to a primary alcohol all in one go (does not form aldehyde in the middle)

Question 4

Reducing agent for reduction back to primary alcohol

Answer 4

LiAlH4 in dry ether

Question 5

Neutralisation of carboxylic acid and carbonate/hydrogencarbonate

Answer 5

Produces salt water and carbon dioxide

Question 6

Observation for reaction of carboxylic acid and carbonate/ hydrogen carbonate

Answer 6

Effervescence in the form of CO2 bubbles produced so this tests for presence of carboxylic acid

Question 7

How much LiAlH4 is needed to reduce carboxylic acid?

Answer 7

4 to 1 carboxylic acid

Question 8

What carboxylic acid can be oxidised?

Answer 8

Only methanoic acid because it has an aldehyde group essentially

Question 9

What carboxylic acid can be oxidised?

Answer 9

Only methanoic acid because it has an aldehyde group essentially

Question 10

Methanoic acid oxidation

Answer 10

To carbonic acid, OHCOOH

Question 11

What is an acyl chloride?

Answer 11

Molecule that contains the group Cl-C=O

Question 12

How to name acyl chlorides

Answer 12

Longest chain hydrocarbon + oyl + chloride

Question 13

How to name acyl chlorides?

Answer 13

Longest chain + oyl + chloride
Eg ethanoyl chloride

Question 14

Carboxylic acid + PCl5

Answer 14

Forms an acyl chloride + POCl3 + HCl

Question 15

Observation of carboxylic acid + PCl5

Answer 15

Steamy fumes of HCl is produced
Acidic = bleaches damp litmus paper red
So can test for presence of carboxylic acid