Chemistry A-Level
pKa
What pKa means in Chemistry A-Level, as defined for AQA.
Definition of pKa
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Reference: AQA
The logarithmic form pKa = −log₁₀Ka, where a smaller value means a stronger acid.
Topics that use pKa
- 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
- acid dissociation constant
- partial dissociation
- ranking acid strength
Using pKa in the exam
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