OCR A-Level Chemistry: Module 6 - Organic Chemistry & Analysis

What does the symbol [H] represent? (1)

Suggest a reagent that would convert the -OH group in phenol to an -O(-) group (1)

1,4-dinitrobenzene is converted to 1,4-diaminobenzene, what type of reaction is this? (1)

State reagents and conditions required to convert 1,4-dinitrobenzene to 1,4-diaminobenzene (2)

Explain how the amino groups in a primary amine allow the molecule to act as a base (2)

State whether you would expect hexane-1,6-diamine to be a stronger or weaker base than 1,4-diaminobenzene. Explain your reasoning (3)

Suggest possible problems of making a chiral drug such as salbutamol and describe two
ways that the pharmaceutical industry might overcome these problems (4)

Explain what is meant by an α-amino acid (1)

Explain the evidence that led scientists to doubt the model proposed by Kekulé (3)

The chemist observed that bromine decolourises when it reacts with phenol
What other observation would she have made? (1)

Cyclohexene also decolourises bromine

Name the organic product formed (1)

Explain the relative resistance to bromination of benzene compared to phenol and compared to cyclohexene (5)

State the general formula of an α-amino acid (1)

The mixture of tripeptides can be analysed by using gas chromatography, coupled with mass spectrometry. Summarise how each method contributes to the analysis (3)

State what is meant by the term zwitterion (1)

What is meant by the term stereoisomer? (1)

How does cis-trans isomerism arise in organic molecules? (1

State a use for Kevlar (1)

Kevlar is formed from a diamine and a dioic acid, what kind of polymerisation is this reaction? (1)

Chlorobenzene can be nitrated to form a mixture of products. Suggest why the reaction forms a mixture of products (1)

State what the biochemist would see when hydroxyethanal reacts with
Tollens’ reagent (1)

The biochemist also reacted hydroxyethanal with acidified dichromate by heating
under reflux. Write an equation for this oxidation. [O] is oxidising agent (2)

The biochemist then reduced hydroxyethanal using aqueous NaBH4.
Write the structural formula of the organic product (1)

What is meant by the term nucleophile? (1)

Describe a simple chemical test that would show that but-2-enal is an aldehyde (2)

Explain why Tollens' reagent test gives a different result for aldehydes and ketones (1)

Tollens’ reagent can be used to identify the aldehyde group in cinnamaldehyde. (6)
• Describe how you would make Tollens’ reagent and carry out this test in the
laboratory.
• Explain what happens to both the Tollens’ reagent and the cinnamaldehyde in
this reaction.

How does gas chromatography separate the compounds in the mixture? (1)

Two compounds pass through a gas chromatogram, what is suggested about the one that comes out first? (1)

Three compounds:

Ketone & primary alcohol (A),

Aldehyde & secondary alcohol (B),

Ketone & tertiary alcohol (C)

Describe chemical tests to distinguish between the compounds (4)

An alcohol is reacted with excess K2Cr2O7/H2SO4 under reflux, state observation during reaction? (1)

Describe a chemical test that you could use to detect the presence of a carbonyl group in an organic compound, reagent and observation (2)

State one possible health risk of a diet that is high in trans oils (1)

A chemical with chiral centres can be synthesised from naturally occuring steroids. Suggest an advantage of having a synthetic route (1)

Explain what is meant by the term condensation polymerisation (1)

Before any skin cream can be sold to the public, it must be tested to ensure it is safe to
use. Suggest why (1)

Methylglyoxal, CH3COCHO, is formed in the body during metabolism.
Describe one reduction reaction and one oxidation reaction of methylglyoxal that could be carried out in the laboratory.
Include reagents, equations and observations (5)

A synthetic polymer can be easily hydrolysed compared with other synthetic polymers, explain why it is thought polymers such as this one are better for the environment (1)

Explain how the student could use infrared spectroscopy to confirm which compound is a
carboxylic acid (1)

The aldehyde has the molecular formula C5H10O.
The 1H NMR spectrum of the aldehyde contains a doublet at δ = 0.9 ppm with a relative peak area of six compared with the aldehyde proton.
Analyse this information to deduce the structure of the aldehyde. Explain your reasoning (3)

State what is meant by retention time (1)

How could a specific carbonyl be identified not using spectroscopy after reaction with 2,4-DNPH? (2)

Outline purification (4)

Phenol undergoes easier nitration than benzoic acid, explain this (3)

Suggest why a polyester is biodegradable (1)

A CHO based molecule is slightly acidic but has no visible change when Na2CO3 is added, suggest the functional group responsible (1)

Explain why phenol is nitrates more readily than benzene (3)

Explain what is meant by molecular ion peak (1)

Explain what is meant by base peak (1)

Name the process by which TLC separates α-amino acids (1)

A student used TLC to separate three different α-amino acids, explain how the student could analyse the chromatogram to identify the α-amino acids present (2)

Several α-amino acids have structures that are very similar. Suggest why this could cause problems when using TLC to analyse mixtures of α-amino acids (1)

Define Rf value (1)

What are the roles of the gas and liquid in gas/liquid chromatography? (2)

Explain how the gas/liquid chromatogram could be used to determine the percentage composition of each component in the mixture (3)