Acid dissociation constant Ka
What Acid dissociation constant Ka means in Chemistry A-Level, as defined for OCR.
Definitions of Acid dissociation constant Ka
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Reference: OCR
For a weak acid HA dissociating in water, HA ⇌ H⁺ + A⁻, it is given by Ka = [H⁺][A⁻]/[HA], where concentrations are equilibrium values.
For a weak monobasic acid HA it is given by the expression Ka = [H⁺][A⁻]/[HA].
Topics that use Acid dissociation constant Ka
- Acids, bases and buffers (OCR A-Level)
Related terms
- acidic buffer
- Amphiprotic
- basic buffer
- Basicity
- Buffer action against added acid and alkali
- Buffer action and pH resistance
- Calibration with buffer solutions
- Care and storage of the pH electrode
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