Organic Chemistry and Analysis | OCR A-Level Chemistry A (H432)

Organic Chemistry and Analysis

184 questions
17 subtopics
Module 6: Organic chemistry and analysis
Component 02 and Component 03

The second half of the organic course: carbonyl compounds and nucleophilic addition, carboxylic acids, esters and acyl chlorides, amines, amino acids and chirality, condensation polymers, carbon-carbon bond formation, and the chromatographic and test-tube analysis that identifies the product..

It covers oxidation and reduction of carbonyls, and the addition of HCN, the nucleophilic addition mechanism, 2,4-DNPH and Tollens' reagent, carboxylic acids: solubility and reactions with metals, carbonates and bases, esterification and the hydrolysis of esters, acyl chlorides and their reactions with alcohols, amines and ammonia, amines as bases, and preparing aliphatic amines, secondary and tertiary amines, and preparing aromatic amines, amino acids, their reactions, and amides, optical isomerism and identifying a chiral centre, condensation polymerisation and the ester and amide linkages, hydrolysing condensation polymers and telling them from addition polymers, nitriles from haloalkanes and from carbonyl compounds, friedel-Crafts reactions and lengthening the carbon chain, thin-layer and gas chromatography, Rf values and retention times, test-tube tests for the organic functional groups and tests for the inorganic ions and interpreting chromatograms.

Sample questions from Organic Chemistry and Analysis

Answer each one closed book first, then open the answer.

Oxidation and reduction of carbonyls, and the addition of HCN

Which ion acts as the oxidising agent when aldehydes are oxidised in acidic solution?

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The dichromate ion, Cr₂O₇²⁻
2,4-DNPH and Tollens' reagent

Why do different carbonyl compounds form derivatives with 2,4-DNPH that can be distinguished from each other?

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Each derivative has a characteristic melting point
Esterification and the hydrolysis of esters

What are the products when an acid anhydride reacts with an alcohol?

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An ester and a carboxylic acid.
Amines as bases, and preparing aliphatic amines

What type of product is formed when an amine reacts with a dilute inorganic acid such as hydrochloric acid?

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An ammonium salt is formed.
Amino acids, their reactions, and amides

What type of reaction occurs when an amino acid reacts with an alcohol to form an ester?

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A condensation reaction between the -COOH group and the -OH group of the alcohol.
Condensation polymerisation and the ester and amide linkages

When acyl chlorides are used as monomers in condensation polymerisation instead of carboxylic acids, what small molecule is eliminated?

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HCl is eliminated rather than water.
Nitriles from haloalkanes and from carbonyl compounds

In the reaction of a haloalkane with CN⁻, which species acts as the nucleophile?

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The CN⁻ ion
Thin-layer and gas chromatography, Rf values and retention times

Why must standards be run under identical conditions when using Rf values for identification?

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Rf values depend on factors such as solvent, temperature, and stationary phase, so conditions must be the same for valid comparison.

The 17 subtopics

One subtopic is one session. Work down the list.

Subtopic	What it covers	Questions
Oxidation and reduction of carbonyls, and the addition of HCN	Recall questions on [O] and [H] notation, oxidising an aldehyde, reducing an aldehyde and a ketone with NaBH₄, and the hydroxynitrile from HCN.	10
The nucleophilic addition mechanism	Recall questions on why the carbonyl carbon is electrophilic, the hydride and cyanide attacks, the intermediate formed, and the protonation that completes it.	11
2,4-DNPH and Tollens' reagent	Recall questions on what each reagent detects, the observations for a positive result, using a 2,4-DNPH derivative to identify a specific compound, and why ketones fail Tollens'.	11
Carboxylic acids: solubility and reactions with metals, carbonates and bases	Recall questions on the hydrogen bonding that makes them soluble, and on the products with reactive metals, carbonates, metal oxides and alkalis.	12
Esterification and the hydrolysis of esters	Recall questions on the acid catalyst and reversibility of esterification, the acid anhydride route, and the products of acid and of base hydrolysis.	10
Acyl chlorides and their reactions with alcohols, amines and ammonia	Recall questions on making an acyl chloride with thionyl chloride, and on the products with water, alcohols, primary and secondary amines and ammonia.	16
Amines as bases, and preparing aliphatic amines	Recall questions on why the nitrogen lone pair makes an amine basic, the salt formed with an acid, and preparing a primary amine from a haloalkane with excess ammonia.	10
Secondary and tertiary amines, and preparing aromatic amines	Recall questions on further substitution to secondary and tertiary amines, and on reducing a nitroarene with tin and hydrochloric acid to give phenylamine.	8
Amino acids, their reactions, and amides	Recall questions on the general formula of an α-amino acid, its reactions with alkali, acid and alcohols, and the structures of primary and secondary amides.	11
Optical isomerism and identifying a chiral centre	Recall questions on what optical isomerism is, non-superimposable mirror images, locating a chiral centre, and why glycine is the exception.	11
Condensation polymerisation and the ester and amide linkages	Recall questions on what is eliminated, which pairs of monomers give a polyester and which a polyamide, and what changes when acyl chlorides are used.	9
Hydrolysing condensation polymers and telling them from addition polymers	Recall questions on the products of acid and base hydrolysis of a polyester and a polyamide, and on identifying which kind of polymer a structure is.	9
Nitriles from haloalkanes and from carbonyl compounds	Recall questions on the cyanide substitution and addition routes, the mechanisms each follows, and reducing or hydrolysing the nitrile afterwards.	11
Friedel-Crafts reactions and lengthening the carbon chain	Recall questions on the reagents and halogen carriers for alkylation and acylation, and on how many carbons each route adds to the chain.	10
Thin-layer and gas chromatography, Rf values and retention times	Recall questions on calculating and using Rf values, retention time, what a peak area represents, and building an external calibration curve.	14
Test-tube tests for the organic functional groups	Recall questions on the tests for alkenes, haloalkanes, phenols, carbonyls, aldehydes against ketones, alcohols and carboxylic acids.	12
Tests for the inorganic ions and interpreting chromatograms	Recall questions on the tests for carbonate, sulfate, the halides and ammonium, and on reading retention times and peak areas from a chromatogram.	9

Organic Chemistry and Analysis is 184 of the 1,913 questions in the guide.Get the guide, £8

How the guide is worked

Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.

Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.

Read the full method, the return schedule and the research behind it.