Organic Chemistry becomes difficult to revise when every reaction is stored as an isolated fact. A map helps you see which functional group changes and which part of the molecule stays the same. The aim is to reconstruct a route and explain it, rather than recognise a colourful chart you have already seen.
Separate AS foundations from later content
Start from the Cambridge 9701 syllabus for 2025–2027, which separates AS and A Level subject content. Mark which reactions and mechanisms belong to your current course stage. Add new material as it is taught, while continuing to practise the earlier functional groups. If the workload has increased sharply, our AS to A2 guide can help you organise the transition.
Give every reaction arrow a complete label
For each route, record the starting structure, product structure, reagent and relevant conditions. Keep observations in a separate column so you do not confuse a colour change with the chemical product. Add a mechanism label only where that mechanism is required. Leaving a box blank is a useful way to identify what you still need to learn.
| Map field | Question to ask | What to check |
|---|---|---|
| Starting compound | Which functional group reacts? | Its position and neighbouring groups |
| Product | What bonds or groups change? | Carbon count and valid bonding |
| Reagent | Which substance causes the change? | Precise identity rather than a vague label |
| Conditions | What conditions select this route? | Solvent, heating or catalyst where relevant |
| Explanation | Why does this transformation occur? | The mechanism or reasoning requested |
Worked example: oxidation of a primary alcohol
Use ethanol, CH₃CH₂OH, as an introductory example. Oxidation with acidified potassium dichromate(VI), with distillation of the aldehyde as it forms, gives ethanal, CH₃CHO. Further oxidation using excess oxidising agent under reflux gives ethanoic acid, CH₃COOH. These alcohol and carbonyl transformations are covered in sections 16 and 17 of the 9701 syllabus.
For your revision card, hide the compound names and reconstruct the structures. Then hide the structures and supply the names. Finally, replace ethanol with propan-1-ol and work out the corresponding aldehyde and carboxylic acid. This small change checks whether you understand the functional-group transformation rather than remember one familiar sequence.
Practise mechanisms as a separate skill
Knowing the final product does not automatically give you a correct mechanism. Draw the reactants clearly, identify where an electron pair starts and where it moves, then show the resulting bond and charge changes. Use the conventions in the syllabus for each required mechanism. Keep free-radical steps distinct from mechanisms that show electron-pair movement.
Use a short recall-and-application cycle
- Choose one functional group and draw its required routes from memory.
- Check missing reagents, conditions and structures against your notes and syllabus.
- Close the notes and redraw the routes you missed.
- Answer an unfamiliar conversion or mechanism question.
- Record whether the mistake involved recall, structure, conditions or explanation.
Return to the same weak route in a later session and change the example molecule. Keep physical and inorganic revision in your weekly timetable so an attractive reaction map does not absorb all your study time. Our past-paper guide explains how to move from topic practice to mixed papers.
Get feedback on the step you cannot explain
Bring an attempted mechanism or an incomplete reaction map to a lesson. It gives a tutor more useful information than simply saying that organic Chemistry is difficult. Explore Chemistry tutoring and our A Level course for support with the topics and paper types you are preparing.
Frequently asked questions
01How do I remember organic Chemistry reactions?
Build small maps around a functional group and label each route with its product, reagent and conditions. Recreate the map from memory, then solve questions with different molecules so you practise applying the pattern.
02Is a reaction map enough for A Level Chemistry?
No. It helps organise recall, but you also need structures, explanations, mechanisms and question practice. Cover the physical, inorganic and practical parts of your syllabus as well.
03Where should a curly arrow start?
For an electron-pair mechanism, start the arrow at the electron pair that moves, represented by a lone pair or a bond. Its end shows where those electrons go. Check charges, bond changes and the required mechanism conventions.
