Esters - PL

Question 1

How to name esters

Answer 1

ABC (alcohol before c.acid)
part with C=O is c.acid
part with C-O is alcohol
….yl ……anoate
https://www.gcsescience.com/ethyl-propanoate.gif Name - ethyl propanoate

Question 2

What type of reaction is used to break an ester and what does it mean

Answer 2

hydrolysis = breaking using water

Question 3

What do you use in the reaction to break an ester

Answer 3

water and a catalyst because just using water is very slow

Question 4

What are the types of catalyst used in breaking an ester

Answer 4

acid or alkali catalyst

Question 5

How to break an ester

Answer 5

doesn’t matter which catalyst = use 4-6mol/dm3 of the catalyst and reflux.
1. break the bond (bond between the double bond O and single bond O)
2. add water to produce the alcohol and carboxylic acid
3. consider if products react with catalyst

Question 6

When breaking an ester will the alcohol and carboxylic acid react with the acid catalyst and what will the final products be

Answer 6

neither will react. Final products = carboxylic acid and alcohol

Question 7

When breaking an ester will the alcohol and carboxylic acid react with the alkali catalyst and what will the final products be

Answer 7

alcohol won’t react but the carboxylic acid will produce a carboxylate ion (salt). Final products = alcohol and carboxylate ion

Question 8

For each catalyst used in breaking ester which are reversible

Answer 8

acid = reversible (lower yield)
alkali = irreversible

Question 9

If ethyl propanoate reacts with water with NaOH catalyst what will the final products be and why

Answer 9

• ethanol as the alcohol part doesn’t react with the catalyst
• sodium propanoate as the carboxylic part with react with the catalyst

https://cdn.savemyexams.com/uploads/2020/12/3.6-Carboxylic-Acids-Derivatives-Hydrolysis-by-Alkali.png