BRAINCAKEThe rate and extent of chemical change
Revision notes for The rate and extent of chemical change in AQA Chemistry (8462). Every lesson in BrainCake comes with R.E.C.I.P.E. recall steps, a quick check and spaced reviews.
- Calculating rates of reactionsThe rate of a reaction tells us how fast reactants are used up or how fast products are made.
- Factors which affect the rates of chemical reactionsReactions go at very different speeds.
- Collision theory and activation energyCollision theory explains how conditions change the rate of a reaction.
- CatalystsA catalyst changes the rate of a chemical reaction but is not used up during the reaction.
- Reversible reactionsIn most reactions the reactants turn into products and that is the end of it.
- Energy changes and reversible reactionsEvery reversible reaction has an energy change in both directions.
- EquilibriumImagine a reversible reaction in a closed container, where nothing can escape.
- The effect of changing conditions on equilibrium (HT only)The relative amounts of all the reactants and products at equilibrium depend on the conditions of the reaction.
- The effect of changing concentration (HT only)Take a reversible reaction at equilibrium: A + B ⇌ C + D.
- The effect of temperature changes on equilibrium (HT only)Changing the temperature of a system at equilibrium also changes the relative amounts of reactants and products.
- The effect of pressure changes on equilibrium (HT only)Pressure only affects a reversible reaction at equilibrium when gases are involved.