4.2.1: Alcohols

Question 1

What is formed when an alcohol reacts with sodium chloride and sulfuric acid?

Answer 1

• Haloalkane
• NaHSO4
• Water

Question 2

Suggest 2 uses of methanol

Answer 2

• Fuel
• Manufacture of esters

Question 3

What type of reaction occurs for
aldehyde + aldehyde = hydroxyaldehyde

Answer 3

Addition

Question 4

Explain the polarity of alcohols compared to alkanes

Answer 4

More polar due to presence of hydroxy groups

Question 5

Explain the solubility of alcohols compared to alkanes

Answer 5

More soluble due to presence of hydroxy groups so more hydrogen bonds can be made with water

Question 6

Explain the volatility of alcohols compared to alkanes

Answer 6

Less volatile due to a higher boiling point as strong hydrogen bonds which require a lot of energy to break

Question 7

What are the products of the combustion of alcohols ?

Answer 7

H20 and CO2

Question 8

What are the conditions and reagents for the oxidations of a primary alcohol ?

Answer 8

K2Cr2O7/ H2SO4 and distillation to aldehyde

K2Cr2O7/ H2SO4 and reflux to carboxylic acid

Question 9

What are the conditions and reagents for the oxidations of a secondary alcohol ?

Answer 9

K2Cr2O7/H2SO4 and reflux to ketone

Question 10

What are the conditions and reagents for the oxidations of a tertiary alcohol ?

Answer 10

Tertiary alcohols can’t be oxidised

Question 11

What is the colour change observed in the oxidation of alcohols and why does it occur ?

Answer 11

Orange to green as the dichromate ion is reduced to a chromium ion

Question 12

What is the product and reagent of the elimination of alcohols

Answer 12

Alkene + H2O
H2SO4

Question 13

What is the product, reagent and mechanism for the production of haloalkanes from alcohols

Answer 13

Haloalkane + water
Sodium halide+ H2SO4
Nucleophilic substitution