WM

Question 1

What is the process of recrystallisation?

Answer 1

Dissolve in minimum amount of hot solvent
Filter off insoluble impurities
Soluble impurities remain –> crystallise

Dry, distil, wash and separate crystals

Question 2

What is the formula of an ether?

Answer 2

R-O-R

Question 3

What are features of a tertiary alcohol?

Answer 3

Cannot be oxidised by dichromate
It can form esters
It can be dehydrated

Question 4

What are the products of salicylic acid + acid anhydride?

Answer 4

CH3COOH
Benzene ring; one -COOH and one group goes
- O - C = O (CH3)

Question 5

How to analyse TLC?

Answer 5

Examine spots
UV/iodine

Question 6

How may NaOH react with aspirin under other conditions?

Answer 6

-OH and -COOH form salts

Question 7

Which impurity may be present in aspirin?

Answer 7

Salicylic acid

Question 8

What do carboxylic/phenols react with?

Answer 8

Alkali
CARBOXYLIC ONLY - CARBONATES
Phenol + acid anhydride forms ester

Question 9

Alcohol to haloalkane

Answer 9

Nucleophilic substitution
NaBr
H2SO4
Reflux

Question 10

Techniques for making a solid organic solvent

Answer 10

Filtration under reduced pressure
Recrystallisation
Melting point determination

Question 11

How do you determine a melting point?

Answer 11

Heat in capillary tube