Chemistry A-Level
control variables
What control variables means in Chemistry A-Level, as defined for AQA.
Definition of control variables
Check what you remember
Read the wording for your board, then hide it and explain control variables in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: AQA
Everything except temperature must be held constant: the concentrations, the total volume, the depth of liquid, the same cross, and ideally the same observer.
Topics that use control variables
- Effect of temperature on reaction rate (AQA A-Level)
Related terms
- area beyond Eₐ
- kinetic energy of particles
- mean energy versus tail
- proportion exceeding Eₐ
- rate of reaction
- rate proportional to 1/t
- temperature and rate
- water bath equilibration
Using control variables in the exam
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