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Flashcards in Alcohol Deck (11)
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1

Physical properties

Less volatile than alkanes
Higher melting points
Greater water solubility than alkanes

2

Why are alcohols soluble in water

Polar OH bond, different electronegativities
Hydrogen bonds form between water and hydroxyl group on the end

3

Why do alcohols have a fairly low boiling point

Hydrogen bonds broken to become a gas
More force needed to break them

4

Solubility of alcohols

Hydroxyl and water molecules form hydrogen bonds
Hydrocarbon chain increases in size, hydroxyl influence decreases, solubility decreases

5

Combustion of alcohols

Exothermic
As number of C increases, quantity of heat released/ mole increases

6

Oxidation of alcohols

Oxidised by K2Cr2O7, acidified by H2SO4
Dichromate (6), orange
Chromium (3) ions, green

7

Primary alcohol oxidation

Distillation, acidified potassium dichromate, aldehyde
Reflux, acidified potassium dichromate, carboxylic acid

8

Oxidation of secondary alcohols

Reflux, acidified potassium dichromate, ketone

9

Oxidation of tertiary alcohols

Do not oxidise

10

Dehydration of alcohols

Water is removed from starting material
Reflux, acid catalyst, gives alkene
Elimination

11

Substitution reactions of alcohols

Alcohol and HX => haloalkane
Reflux, sulphuric acid and sodium halide
Release water