AQA A-level Chemistry 7405: Command words and keywords

AQA A-level Chemistry (7405) uses the standard AQA Science command words. A-level expects more depth and application to unfamiliar contexts. Mark schemes reward syllabus terminology used correctly in context.

Command words

Command word	What to do	Common mistake
State	Short answer	Overwriting
Define	Precise meaning	Vague
Describe	What happens; no “why”	Adding explanation
Explain	Why/how; use “because”	Only describing
Suggest	Apply to new context	Textbook recall
Calculate	Show working; units	Missing working
Draw	Displayed formula; correct structure	Wrong bonds
Predict	What will happen	Unsupported
Compare	Similarities and differences	Listing separately
Evaluate	Judge; conclude with evidence	No conclusion

Keywords

Term	Use correctly	Avoid
Electrophile	Electron-deficient	Nucleophile
Nucleophile	Electron-rich	Electrophile
Hydrogen bonding	H with N, O or F	”Strong bond”
Activation energy	Minimum for reaction	”Energy”
Catalyst	Speeds up; unchanged	”Used up”
Le Chatelier	Oppose change	”Balance”
Oxidation	Loss of electrons	Gain of oxygen only
Reduction	Gain of electrons	Loss of oxygen only
Brønsted-Lowry acid	H⁺ donor	”Sour”
Brønsted-Lowry base	H⁺ acceptor	”Bitter”
Buffer	Resists pH change	”Neutraliser”
Enthalpy change	ΔH	”Heat”

Tips for Chemistry 7405

1. Suggest—apply to the specific scenario
2. Show working in calculations; include units
3. State symbols in equations when required
4. Past papers + mark schemes show acceptable wording

How Tutopiya helps

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Based on AQA A-level Chemistry 7405 specification. OxfordAQA International A-level Chemistry uses similar approaches.