Chemical Equilibrium

What the page covers

The resources follow the usual route through equilibrium. They begin with reversible reactions and the idea of a dynamic balance, then move to the equilibrium constant, the effect of changing conditions, and industrial uses.

• The mind map Reversible Reactions starts with reactions that work in both directions.
• The mind map Dynamic Equilibrium explains that forward and backward rates are equal and that a closed system is needed.
• The mind map Equilibria sets out Kc as a ratio of product and reactant concentrations.

Where to start

Begin with the mind maps Chemical Equilibrium and Dynamic Equilibrium. They give the definition in a few lines. Then open Reversible Reactions to see examples such as thermal decomposition.

Next, move to changing conditions. The Equilibrium Revision Mindmap covers Kp, Kc and the effects of temperature, concentration, pressure and a catalyst. The map OCR A2 Chemistry Le Chatelier's Principle goes further on pressure and temperature.

Using quizzes with maps

Read a map first, then take a quiz without looking. The quiz Equilibrium (paper 1 style questions) suits exam practice. Another quiz asks what happens when pressure rises in a closed gaseous system where the forward reaction makes 2 mol and the reverse makes 3 mol. Go back to the map for any answer you miss.

For recall, the flashcard deck Aqueous Systems 3.6 covers solubility and Ks, the constant for a saturated solution of a sparingly soluble compound. Other decks cover Kp, acid-base equilibria and the Haber Process.

Where it fits

This unit sits in the Physical Chemistry strand of Chemistry. The resources mention A-level Chemistry, GCSE Chemistry, IGCSE Chemistry, AQA GCSE Chemistry, IB and IB Chemistry, so most suit school students. Teachers can use the notes and slide sets in lessons.

Choose one map today, then test yourself with a quiz and see what you remember.