1. Alcohols… Alcohols are a homologous series where:
No double bonds present
General Formula CnH2n+1OH
All exhibit Hydrogen Bonds
There are three types;
Primary
Secondary
Tertiary

2. Alcohols… Alcohols undergo the following reaction types: Combustion
Oxidation
using Potassium Dichromate
Esterification
Dehydration

3. Alcohols…
Primary alcohols have the functional group at the end of the chain.
Attached to the same carbon as the OH is:
1 alkyl group
2 Hydrogens
e.g. Butan-1-ol

4. Alcohols… Primary alcohols can be oxidised to form carboxyl compounds:
Under DISTILLATION conditions
CH3CH2CH2CH2OH + [O]  CH3CH2CH2CHO
Under REFLUX conditions
CH3CH2CH2CH2OH + [O]  CH3CH2CH2COOH
Solution will change from orange to green

5. Alcohols…
Secondary alcohols have the OH group in the middle of the chain.
Attached to the same carbon as the OH is:
2 alkyl groups
1 Hydrogen
e.g. Butan-2-ol

6. CH3CH2CH(OH)CH3 + [O]  CH3CH2COCH3
Alcohols…
Secondary alcohols can be oxidised to form ketones:
Under REFLUX conditions
CH3CH2CH(OH)CH3 + [O]  CH3CH2COCH3
Solution will change from orange to green

7. Alcohols…
Tertiary alcohols have the OH group next to two branches of the chain.
Attached to the same carbon as the OH is:
3 alkyl groups
0 Hydrogens
e.g. 2-methylpropan-2-ol

8. Alcohols… Tertiary alcohols cannot be oxidised, under any conditions.
Under REFLUX conditions
CH3C(CH3)(OH)CH3 + [O] 
Solution will remain orange

9. Alcohols… D

10. Alcohols…
We can use oxidation reactions (and the products) to identify unlabelled primary, secondary and tertiary alcohols.
Suggest a method to do so.

11. Alcohols…
Heat all three unknowns under reflux with Potassium Dichromate.
Mixture containing tertiary alcohol will remain orange.
Test the green solutions with sodium carbonate:
Carboxylic acid (from primary alcohol) will fizz
Ketone (from secondary alcohol) will not

12. Alcohols…
Alcohols have higher boiling points than their base alkanes due to the presence of two types of intermolecular forces:
Instantaneous dipole-induced dipole from the alkyl chain
Hydrogen bonds from the –OH group
Alkanes only have id-id which require less energy to overcome.

13. Alcohols…
Explain the trend in the boiling point of the alcohols (4 marks)
Increased contact between the hydrocarbon chains
Increased Instantaneous dipole – induced dipole
Increased energy required to overcome IM forces
Increased boiling point

14. Alcohols…
Alcohols are less volatile than their corresponding alkanes due to the strength of their Hydrogen bonds.
Volatility, and therefore flammability, decreases as the chain gets longer.

15. Alcohols…
Alcohols are soluble in water due to their similar intermolecular forces – both exhibit Hydrogen Bonds

16. Haloalkanes… Haloalkanes are a homologous series where:
No double bonds present
General Formula CnH2n+1X
All are Polar

17. Haloalkanes…
The reactivity of a haloalkane is determined by its carbon-halogen bond.
The weaker the bond the more reactive the compound.
Iodoalkanes are MUCH more reactive than fluoroalkanes.

18. Haloalkanes…
Explain why C-X bond strength decreases down group (4 marks)
Atomic radius increases
Distance of covalent bond from nucleus increases
Shielding increases
Less energy required to break the bond

19. Haloalkanes…
Haloalkanes contain the subclass of CFCs (chlorofluorocarbons) which are used as:
Refrigerants
Fire safety equipment
In the atmosphere CFCs are inert and non-toxic
In the stratosphere CFCs deplete ozone

20. Haloalkanes… Homework:
Research the Montreal Protocol and the effects of ozone depletion.