Curly arrow conventions
What Curly arrow conventions means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of Curly arrow conventions
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Reference: OCR
One curly arrow runs from the lone pair to the δ⁺ carbon, and a second shows the C–X bond breaking with both electrons moving onto the halogen.
Each arrow is drawn from an electron source to an electron-poor atom and represents a pair of electrons moving in one direction.
Every curly arrow must start from a lone pair or from a bond; an arrow starting anywhere else is penalised each time it appears.
The formation of a covalent bond is shown by a curly arrow that starts from a lone electron pair or from another covalent bond.
The mechanism can be shown with curly arrows from the nucleophile to the δ⁺ carbon and from the C=O π bond to oxygen.
Topics that use Curly arrow conventions
- Acylation (A-level only) (AQA A-Level)
- Reaction mechanisms (AQA A-Level)
- Alkenes (OCR A-Level)
- Carbonyl compounds (OCR A-Level)
- Haloalkanes (OCR A-Level)
Related terms
- Heterolytic fission
- Homolytic fission
- 2,4-dinitrophenylhydrazine test
- 2,4-dinitrophenylhydrazone
- acid anhydride
- Acidified dichromate(VI) as oxidising agent
- acidified potassium dichromate(VI)
- Addition polymerisation
Using Curly arrow conventions in the exam
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