Chemistry A-Level
Negative sign
What Negative sign means in Chemistry A-Level, as defined for OCR.
Definition of Negative sign
Check what you remember
Read the wording for your board, then hide it and explain Negative sign in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: OCR
The negative sign converts the negative logarithm of a dilute acid into a positive pH, so omitting it would report a negative pH for an ordinary acid.
Topics that use Negative sign
- Acids, bases and buffers (OCR A-Level)
Related terms
- Acid dissociation constant Ka
- acidic buffer
- Amphiprotic
- basic buffer
- Basicity
- Buffer action against added acid and alkali
- Buffer action and pH resistance
- Calibration with buffer solutions
Using Negative sign in the exam
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