Chemistry (Combined Science) · GCSE · OCR · OCR GCSE Combined Science A (Gateway Science) — Chemistry — Foundation (J250) · Specification point · C5.2 · Monitoring and controlling chemical reactions
Read Notes
Read clear notes for this topic.
Practice Questions
Coming soon
Exam Questions
Coming soon
Flashcards
Flip through flashcards to lock it in.
Lesson
Coming soon
Ask Sage
Get help from Sage on this topic.
C5.2 Equilibria
Summary In a reaction, when the rate of the forward reaction equals the rate of the backwards reaction, the reaction in a closed system is said to be in equilibrium. Underlying knowledge and understanding Learners will be familiar with representing chemical reactions using formulae and using equations.
Common misconceptions Learners often do not recognise that when a dynamic equilibrium is set up in a reaction the concentration of the reactants and products remain constant. They think that the concentrations of all substances are equal. Learners also sometimes perceive a dynamic equilibrium as two reactions.
| Reference | Mathematical learning outcomes | Maths skills |
|---|---|---|
CM5.2i | arithmetic computation, ratio when measuring rates of reaction | M1a, M1c |
CM5.2ii | drawing and interpreting appropriate graphs from data to determine rate of reaction |
M4b, M4c |
CM5.2iii | determining gradients of graphs as a measure of rate of change to determine rate | M4d, M4e |
CM5.2iv | proportionality when comparing factors affecting rate of reaction | M1c |
| Learning outcomes | To include | Maths | Working scientifically | Practical suggestions |
|---|---|---|---|---|
C5.2a recall that some reactions may be reversed by altering the reaction conditions | M1a, M4b, M4c | |||
C5.2b recall that dynamic equilibrium occurs in a closed system when the rates of forward and reverse reactions are equal | M4b, M4c |