3.3.5.2 Oxidation of alcohols

Question 1

What is the difference between a primary, secondary and tertiary alcohol?

Answer 1

Primary: OH is connected to a carbon which is connected to a further carbon
Secondary: carbon is connected to two others
Tertiary: carbon is connected to three others

Question 2

Can primary alcohols be oxidised?

Answer 2

Primary alcohols can be oxidised to aldehydes which can be further oxidised to carboxylic acids
Oxidising agent is represented as [O]
Alcohol to aldehyde: heat, distillation, can have an oxidizing agent, partially oxidized
Aldehyde to carboxylic acid: heat, oxidised

Question 3

Can secondary alcohols be oxidised?

Answer 3

Secondary alcohols can be oxidised to ketones

Ketones cannot be oxidised because oxidation would need a c-c bond to break

Question 4

Can tertiary alcohols be oxidised? Why?

Answer 4

They are not easily oxidised

Oxidation would need a c-c bond to break

Question 5

Draw the two reactions of the distillation and reflux of alcohols

Answer 5

See card

Question 6

Draw the reaction of the oxidation of secondary alcohols to ketones

Answer 6

See card

Question 7

What substance can be used to oxidise alcohols?

Answer 7

Acidified potassium dichromate where orange ions are reduced to green ions

Question 8

What are the conditions required to oxidise an alcohol to an aldehyde?

Answer 8

Distillation apparatus
Potassium dichromate as an oxidising agent, represented as [O]
Dilute acid
Gently heated
Reciever cooled to stop evaporation

Question 9

What are the conditions required to oxidise an alcohol to a carboxylic acid?

Answer 9

Reflux apparatus
Concentrated sulfuric acid
Twice as much of the oxidising agent compared to distillation
Carboxylic acid is distilled at the end