Key Definitions

Part of Equilibrium (HT) · Section 7 of 14

DefinitionsUnit: Rates of ReactionGCSE

This definitions covers Key Definitions within Equilibrium (HT) for GCSE Chemistry. Revise Equilibrium (HT) in Rates of Reaction for GCSE Chemistry with 23 exam-style questions and 18 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 7 of 14 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.

📖 Key Definitions

Dynamic equilibrium: A state reached in a closed system when the forward and backward reaction rates are equal, so concentrations remain constant. Both reactions still occur simultaneously.

Le Chatelier's Principle: If a system at equilibrium is disturbed by a change in conditions, the equilibrium position will shift in the direction that opposes the change.

Equilibrium position: A description of whether the equilibrium mixture contains mostly products (right) or mostly reactants (left), or approximately equal amounts.

Closed system: A system from which no matter can enter or escape, allowing equilibrium to be established.

Practice questions for Equilibrium (HT)

At dynamic equilibrium, which of the following is true?

  • A. The rate of the forward reaction equals the rate of the reverse reaction
  • B. The concentrations of reactants and products are always equal
  • C. The forward reaction stops and only the reverse reaction continues
  • D. All chemical reactions have stopped
1 markfoundation

Explain the effect of increasing temperature on the position of an equilibrium where the forward reaction is exothermic.

2 marksstandard

Quick recall flashcards

What does 'dynamic equilibrium' mean?
Forward and backward reactions happen at the same rate, so concentrations stay constant
What conditions are needed for equilibrium?
A closed system (nothing can escape) and a reversible reaction

23 questions on Equilibrium (HT) — practise free

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