Topic 20
Organic
Synthesis
Topic 20 closes Unit 5 by pulling the organic chemistry of the whole course together: deducing empirical, molecular and structural formulae from combustion analysis, percentage composition, characteristic reactions and spectra; lengthening the carbon chain with Grignard reagents; predicting the properties of unfamiliar compounds, planning reaction schemes of up to four steps, and selecting procedures and control measures from hazard data; the preparation of aspirin (Core Practical 16); and the techniques used to prepare and purify organic compounds, from reflux and recrystallisation to steam distillation and melting and boiling temperature determination.
Revision Notes
7 revision notes, in the order the specification teaches them.
Deducing Formulae from Analytical Data
Deducing empirical, molecular and structural formulae from combustion analysis, percentage composition and spectra.
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Identifying Functional Groups by Chemical Tests
Identifying functional groups by chemical tests and predicting the properties and reactions of unfamiliar compounds.
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Grignard Reagents and Carbon–Carbon Bond Formation
Forming carbon–carbon bonds in synthesis: Grignard reagents with carbon dioxide and carbonyl compounds, and the nitrile route.
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Planning a Synthetic Route
Planning multi-step organic synthesis routes: the reaction map, working backwards from the target.
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Choosing Procedures and Managing Hazards
Selecting and justifying practical procedures for organic reactions and choosing control measures from hazard data.
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Preparing and Purifying Organic Solids
Preparing and purifying organic solids: reflux, filtration, recrystallisation, drying and melting temperature determination.
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Purifying Liquids: Distillation, Steam Distillation and Solvent Extraction
Purifying organic liquids: distillation, steam distillation, solvent extraction, drying and checking purity.
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Grignard Reagents Map
Edexcel International A Level Chemistry · Unit 5 · Topic 20
Every reaction on one A4 page: reagents, conditions and reaction type for each arrow, colour coded, with the key tests.
Formulae and Structures Summary Map
Edexcel International A Level Chemistry
Percentage composition, combustion analysis, chemical tests, and mass, infrared and NMR spectra.
Grignard and Routes Summary Map
Edexcel International A Level Chemistry
Grignard reagents, new C–C bonds, aliphatic and aromatic routes, and working backwards.
Practical Techniques Summary Map
Edexcel International A Level Chemistry
Reflux, distillation, washing and drying, recrystallisation, melting temperature, and hazards.
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Specification
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20.1
20.2
20.3
- i
be able to use knowledge of organic chemistry contained given in this specification to solve problems such as: predicting the properties of unfamiliar compounds containing one or more of the functional groups included in the specification and explain these predictions
Revise - ii
be able to use knowledge of organic chemistry contained given in this specification to solve problems such as: planning reaction schemes of up to four steps, recalling familiar reactions and using unfamiliar reactions given sufficient information
Revise - iii
be able to use knowledge of organic chemistry contained given in this specification to solve problems such as: selecting suitable practical procedures for carrying out reactions involving compounds with functional groups included in this specification
Revise - iv
be able to use knowledge of organic chemistry contained given in this specification to solve problems such as: identifying appropriate control measures to reduce risk based on data of hazards
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20.4
- 20.4
CORE PRACTICAL 16 The preparation of aspirin.
20.5
- i
understand the following techniques used in the preparation and purification of organic compounds: refluxing
Revise - ii
understand the following techniques used in the preparation and purification of organic compounds: purification by washing, including with water and sodium carbonate solution
Revise - iii
understand the following techniques used in the preparation and purification of organic compounds: solvent extraction
Revise - iv
understand the following techniques used in the preparation and purification of organic compounds: recrystallisation
Revise - ix
understand the following techniques used in the preparation and purification of organic compounds: boiling temperature determination
Revise - v
understand the following techniques used in the preparation and purification of organic compounds: drying
Revise - vi
understand the following techniques used in the preparation and purification of organic compounds: distillation
Revise - vii
understand the following techniques used in the preparation and purification of organic compounds: steam distillation
Revise - viii
understand the following techniques used in the preparation and purification of organic compounds: melting temperature determination
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