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.
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.
Practice questions for Equilibrium (HT)
At dynamic equilibrium, which of the following is true?
Explain the effect of increasing temperature on the position of an equilibrium where the forward reaction is exothermic.