AS 2 Chemistry 2.6 Alcohols

?
Preparation of Alcohols
Conditions:
Products:
Reaction Type:
Conditions:Heat under reflux with an aqueous K/Na OH
Products:Alcohol
Reaction Type: Nucleophilic Subtsitution
1 of 9
Colour of flame for combustion of alcohols
clean blue/ yellow flame
2 of 9
How can O-H bond break
RO----H
R----OH
3 of 9
Alcohols with Sodium
Conditions:
Products:
Observations:
Example:
Conditions: small piece of a sodium metal added to alcohol
Products: Sodium alkoxide and hydrogen
Observations: Effervescence
Example: 2C2H5OH + Na = 2C2H5O-Na+ H2
Oxidation and reduction occurs
Remember to dhow charges
4 of 9
Alcohols with HBr
Conditions:
Products:
Reaction Type:
Conditions: heat under reflux with HBr. HBr formed in situ as NaBr and H2SO4
Products: Halogenoalkane and water
Reaction Type: Nucleophilic Substitution
5 of 9
Alcohols with phosphorus pentachloride
Equation:
Conditions:
Products:
Observations:
Equation: C2H5OH + PCL5 = C2H5CL + POCL3 + HCL
Conditions: in a fume cupboard add solid PCL5 tp alcohol
Products: halogenoalkane, phosphorus oxychloride, hydrogen chloride
Observations: solid disappears, misty fumes (HCL), mixture warms
6 of 9
Oxidation with acidified potassium dichromate
What is the oxidising agent/ reactant?
What is colour change?
K2Cr2O7 in DILUTE H2SO4
Orange to green and change in smell
7 of 9
Oxidation with acidified potassium dichromate primary alcohols products?
1. Aldehydes R-C-H with C=O
2. Carboxylic acids R-C-OH with C=O

If aldehyde is desired product it must be distilled off
If carboxylic is desired then refluxing carried out
8 of 9
Oxidation with acidified potassium dichromate (refluxed) secondary alcohols products?
Ketone R-C-R with C=O
9 of 9

Other cards in this set

Card 2

Front

Colour of flame for combustion of alcohols

Back

clean blue/ yellow flame

Card 3

Front

How can O-H bond break

Back

Preview of the front of card 3

Card 4

Front

Alcohols with Sodium
Conditions:
Products:
Observations:
Example:

Back

Preview of the front of card 4

Card 5

Front

Alcohols with HBr
Conditions:
Products:
Reaction Type:

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Alcohols resources »