Chemistry A-Level
constant pressure
What constant pressure means in Chemistry A-Level, as defined for AQA.
Definition of constant pressure
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Reference: AQA
The condition under which enthalpy change is measured, as in an open beaker or a polystyrene cup at constant atmospheric pressure.
Topics that use constant pressure
- Enthalpy change (AQA A-Level)
Related terms
- bond breaking is endothermic
- bond making is exothermic
- enthalpy change
- enthalpy profiles
- per mole quantities
- products minus reactants
- sign of ∆H
Using constant pressure in the exam
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