closed system
What closed system means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of closed system
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Reference: AQA
A closed system is required so that no substance enters or leaves, since anything that escapes cannot come back.
A system in which no reactant or product can enter or leave.
Topics that use closed system
- Chemical equilibria and Le Chatelier's principle (AQA A-Level)
- Chemical equilibrium (OCR A-Level)
Related terms
- constant concentrations
- dynamic equilibrium
- equal forward and reverse rates
- homogeneous equilibria
- Le Chatelier's principle
- position of equilibrium
- Calculating Kc from equilibrium concentrations
- compromise pressure
Using closed system in the exam
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