Alcohols

Question 1

Physical properties of alcohols

Answer 1

• volatile @ room temp and pressure

- does not conduct electricity in any states

Question 2

Trend down the homologous series

Answer 2

• solubility decreases

- MP/BP increases (intermolecular forces of attraction increase)

Question 3

Alcohol rxns

Answer 3

1. Combustion
2. Oxidation
   - O.A
   - atmospheric oxygen

Question 4

Oxidation (O.A)

Answer 4

• lab
• heated mixture of ethanol and acidified potassium manganate (VII)
• forms ethanoic acid and water
• redox rxn
• KMO4 reduced, purple to colourless
• ethanol (R.A) oxidised to ethanoic acid
• draw structural formula

Question 5

Oxidation (atmospheric oxygen)

Answer 5

• oxidised in presence of certain bacteria
• acid and water
• write out eqn

Question 6

How to make ethanol

Answer 6

1. Hydration of ethene

2. Fermentation of glucose soln

Question 7

Fermentation of glucose soln

Answer 7

1. Absence of O2
   - so ethanol produced won’t be oxidised by O2 in air to form acid
2. 20- 40 degrees celcius
   - too high: denature
   - too low: inactive
3. Presence of yeast
   - enzymes in yeast act as catalyst

Question 8

Hydration of ethene

Answer 8

• 300 degrees celsius
• 60 atm
• Phosphoric acid H3PO4 catalyst