Chemistry A-Level
acid dissociation constant
What acid dissociation constant means in Chemistry A-Level, as defined for AQA.
Definition of acid dissociation constant
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Reference: AQA
The equilibrium constant for the dissociation of a weak acid, given by Ka = [H⁺][A⁻]/[HA], with units mol dm⁻³.
Topics that use acid dissociation constant
- Weak acids and bases, Ka, for weak acids (A-level only) (AQA A-Level)
Related terms
- approximations
- comparing rates
- position of equilibrium
- strength versus concentration
- partial dissociation
- pKa
- ranking acid strength
Using acid dissociation constant in the exam
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