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Northern IrelandChemistry

Unit 2 Further Chemical Reactions, Rates and Equilibrium, Calculations and Organic Chemistry

4 dot points across 4 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

Why do the rate factors work, and how do catalysts speed reactions up?

Collision theory, activation energy, how concentration, temperature and surface area change the frequency and energy of collisions, and how catalysts work by lowering activation energy.
A CCEA GCSE Chemistry answer on collision theory, covering how successful collisions need enough energy (the activation energy), how each rate factor changes the frequency or energy of collisions, and how catalysts speed reactions by providing a lower-activation-energy pathway.
9 min answer →

How do reactions release or take in energy, and how do we measure it?

Exothermic and endothermic reactions, energy level diagrams, and measuring temperature changes using calorimetry to compare the energy released by fuels.
A CCEA GCSE Chemistry answer on energy changes, covering exothermic and endothermic reactions, energy level diagrams and activation energy, and how calorimetry is used to measure and compare the energy released when fuels burn.
9 min answer →

What affects how fast a reaction goes, and how do we measure it?

The factors that affect the rate of reaction (concentration, temperature, surface area and catalysts), how rate is measured by gas volume or mass loss, and interpreting rate graphs.
A CCEA GCSE Chemistry answer on rates of reaction, covering how concentration, temperature, surface area and catalysts change the rate, how rate is measured by following gas volume or mass loss, and how to read and interpret rate graphs.
9 min answer →

What is a reversible reaction, and how is the Haber process optimised?

Reversible reactions and dynamic equilibrium, how changing conditions shifts the position of equilibrium, and the conditions used in the Haber process to make ammonia.
A CCEA GCSE Chemistry answer on reversible reactions and equilibrium, covering dynamic equilibrium in a closed system, how changing temperature, pressure and concentration shift the equilibrium, and the conditions used in the Haber process to make ammonia as a compromise.
9 min answer →