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Why do alcohols have a higher boiling point than their corresponding alkanes?

The -OH group on the alcohol is able to form hydrogen bonds which require more energy to break


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

Primary: -OH group bonded to a carbon bonded to one other carbon

Secondary: -OH group bonded to a carbon bonded to two other carbons

Tertiary: -OH group bonded to a carbon bonded to three other carbons


Oxidation of primary alcohols

Products: Aldehyde made first, if there is excess oxidsing agent then a carboxylic acid is formed

Oxidsing agent: Acidified potassium dichromate (VI)

Final Colour of reaction mixture: Green


Oxidation of secondary alcohols

Products: Ketone

Oxidsing agent: Acidified potassium dichromate (VI)

Final colour of reaction mixture: Green


Oxidation of tertiary alcohols

Products: Does not oxidise

Final colour of reaction mixture: Orange


How does reflux work

Liquid is boiled in a vertically mounted condenser so the vapour condenses and returns back into the reaction mixture

Used for heating volatile and flammable liquids


Dehydration of alcohols

Alcohols can loose a molecule of water to form an alkene

Conditions: Alumina (Al2O3) catalyst at 300°C OR reflux with concentrated sulphuric acid

Dehydration is an example of a elimination reaction


Substitution reactions will alcohols

Nucleophilic substitution with halide ions in the presence of a strong acid


Esterification with carboxylic acids and acid anhydrides

Carboxylic acid:
Alcohol + Acid --> Ester + Water
Small amount of concentrated acid as catalyst
Named by alcohol then acid

Acid anhydride:
Alcohol + Acid anhydride --> Ester + Acid
Higher yelid of ester
Named by alcohol then anhydride



General formula of R-O-R

Structural isomers of alcohols


Which molecules contain a hydroxyl group

Alcohols, phenols, and carboxylic acid


The order of acidic strength; water, carboxylic acids, phenol, alcohol

Alcohol < Water < Phenol < Carboxylic Acids


Reactions with carbonates

Only carboxylic acids have a high enough concentrations of H+ ions to produce carbon dioxide on reactions with carbonates

Alcohols and phenols will not react


How to test for phenols

Reaction with iron (III) chloride

If phenol present, the mixture turns purple


Ester formation with phenols

Phenol + Acid anhydride --> Ester + Acids
Under alkaline conditions

Phenols do not reaction with carboxylic acids to produce esters


Equation linking speed of light, wavelength, and frequency

Speed of light = Wavelength x Frequency


What does quantise mean

Molecules must take a small number of definite energy values rather than any energy values


Different types of bond deformation

-Symmetric stretch
-Asymmetric stretch
-Symmetric bend


Two most important regions on IR spectra

-OH group, around 3000
C double bond O, around 1600


Fingerprint region

The region below 1500 which is characteristic of the particular molecule


What can be told from mass spectrometry

-The molecular ion, M+
-The fragment pattern
-The relative abundance of fragment ions



1) Seleft a solvent in which the desired substance is very soluble at high temperatures and and insoluble at low temperatures
2) Dissolve the mixture in the minimum quantity of hot solvent to better the yield
3) Filter to remove any insoluble impurities
4) Leave to cool until crystals form
5) Collect crystals by vacuum filtration
6) Leave the crystals to dry


Thin Layer Chromatography

Used to test the purity of a substance


Melting point determination

Used to test the purity of substances. A pure compound should melt within 0.5°C of it's true melting point