Oxidation of alcohols

Which molecule(s) would form a ketone group when oxidised?

A 1, 2 and 3

B Only 1 and 2

C Only 2 and 3

D Only 1

This question is about reactions of alcohols.

There are 4 structural isomers of C₄H₁₀O that are alcohols: CH₃CH₂CH₂CH₂OH CH₃CH₂CHOHCH₃ (CH₃)₂CHCH₂OH (CH₃)₃COH

Alcohols take part in many different types of reaction, including

• elimination

• oxidation

• substitution

• esterification.

For each type of reaction, choose appropriate reagent(s) and/or catalyst, and show the organic product formed.

Elimination reaction of CH₃CH₂CH₂CH₂OH

Reagent(s) and/or catalyst

organic product

Oxidation reaction of CH₃CH₂CHOHCH₃

Reagent(s) and/or catalyst

organic product

Substitution reaction of (CH₃)₂CHCH₂OH

Reagent(s) and/or catalyst

organic product

Esterification reaction of (CH₃)₃COH

Reagent(s) and/or catalyst

organic product

This question is about alcohols.

An unsaturated alcohol has 6 carbon atoms and contains one C=C bond.

Construct an equation for the complete combustion of this alcohol.

Compound C, shown below, is refluxed with excess acidified potassium dichromate(VI) to form a single organic product and one other product.

Complete the equation for this reaction.

Compound C

Draw the structures of the three isomers of C₇H₁₀ formed from compound D.

A student converts compound D into a diiodoalkane.

Suggest suitable reagents for this reaction.

There are 4 structural isomers of C₄H₁₀O that are alcohols.

A student predicts that these structural isomers could be distinguished using carbon-13 NMR spectroscopy.

Explain whether the student is correct.

In your answer, show how the peaks in the carbon-13 NMR spectra are linked to the structure of each alcohol isomer.

This question is about the chemistry of aromatic compounds.

What chemical test(s) could be used to confirm the presence of the phenol group in compounds K and L ?

A student thought that¹³C NMR spectroscopy could be used to distinguish between compounds J, K and L.

Explain, with reasoning, whether the student is correct.

Compound J is substituted at the 2-and 4-positions by chlorine in the presence of a catalyst.

Outline the mechanism for the 4 substitution of compound J by chlorine in the presence of a catalyst.

Show the role of the catalyst.

Compounds K and L react with chlorine much more readily than compound J.

Explain why.

Compound J, C₆H₅CH₂CH₂OH, is reacted with acidified potassium dichromate(VI) under reflux to form organic product M.

Write an equation for this reaction.

Use [O] to represent the oxidising agent and show the structure of M.

A two-stage synthesis of an amine from compound J is shown below.

Add the reagents for each stage of this synthesis.

Compound J

Which compound can be refluxed with acidified potassium dichromate(VI) to form an organic product with molecular formula C₅H₈O₂?

Alcohols can be used to prepare organic compounds with different functional groups.

HO(CH₂)₄OH can be oxidised to form HOOC(CH₂)₂COOH.

State the reagents and conditions and write an equation for this oxidation.

In the equation, use [O] for the oxidising agent.

Reagents and conditions:........

Equation:

HOOC(CH₂)₂COOH is soluble in water.

Explain, using a labelled diagram, why HOOC(CH₂)₂COOH is soluble in water.

HOOC(CH₂)₂COOH and HO(CH₂)₄OH react together to form polymer E.

Draw one repeat unit of polymer E.

The functional groups should be clearly displayed.

Governments are encouraging the development of biodegradable polymers to reduce dependency on persistent plastic waste derived from fossil fuels.

Polymer E is a biodegradable polymer.

Suggest why polymer E is able to biodegrade.

In Step 1, sodium carbonate, Na₂CO₃, makes the reaction mixture alkaline.

Write an ionic equation to show how carbonate ions form an alkaline solution in water.

In Step 2, explain why the mixture must be acidified so that crystals of benzoic acid appear.

Write the overall equation for the preparation of benzoic acid from phenylmethanol.

Use [O] for the oxidising agent.

Calculate the percentage yield of benzoic acid.

Give your answer to 3 significant figures.

In Step 3, describe how the student can recrystallise the impure crystals to obtain pure benzoic acid.

This question is about reactions of organic compounds containing carbon, hydrogen and oxygen.

A chemist investigates two reactions of alcohol A, shown below.

What is the systematic name of alcohol A ?

What is the structural formula of alcohol A ?

The chemist heats alcohol A with an acid catalyst to form a mixture containing alkenes.

Draw the structures of the two alkenes formed in this reaction.

The chemist heats alcohol A with sodium chloride and sulfuric acid.

Construct a balanced equation for this reaction. Show structures for the organic compounds in your equation.

This question is about alcohols.

Construct an equation for the complete combustion of an unsaturated alcohol with 5 carbon atoms.

Many alcohols, including ethanol, are soluble in water.

Explain, with the aid of a diagram, why ethanol is soluble in water.

Include relevant dipoles and lone pairs.

The solubility of hexan-1-ol and hexane-1,6-diol in water is shown below in Table 19.1

Explain the difference in solubility of hexan-1-ol and hexane-1,6-diol.

Alcohols are important in organic synthesis and can be formed by the reduction of carbonyl compounds.

Complete the flowchart by filling in each box.

What is the name of compound K ?

Butan-1-ol can be oxidised to form two different organic products, depending on the reaction conditions used.

Describe both oxidation reactions of butan-1-ol.

For each reaction include

• the structure of the organic product

• a balanced equation

• the essential reaction conditions.

In your equations you may use [O] to represent the oxidising agent.