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Chemistry 0620

6. Chemical reactions

Physical and chemical change, rate of reaction, reversible reactions and equilibrium, and redox.

  1. 6.1

    Physical and chemical changes

    How to tell a chemical change from a physical one.

    Full lesson1 questions3 cards
    • 6.1.1Identify physical and chemical changes and describe the differences between them.
  2. 6.2

    Rate of reaction

    Collision theory and the effects of concentration, temperature, surface area, pressure and catalysts.

    Full lesson3 questions4 cardsSimulationReview first: 5.1
    • 6.2.1Describe how to measure rate of reaction by gas volume or mass loss.
    • 6.2.2Explain the effects of concentration, pressure, surface area, temperature and catalysts using collision theory.
    • 6.2.3Interpret rate graphs, including the meaning of the gradient and the point where the reaction finishes.
  3. 6.3

    Reversible reactions and equilibrium

    The ⇌ symbol, dynamic equilibrium, and the effect of changing conditions.

    Full lesson2 questions4 cardsReview first: 6.2
    • 6.3.1Describe a reversible reaction and the characteristics of dynamic equilibrium in a closed system.
    • 6.3.2Predict the effect of changing temperature, pressure or concentration on the position of equilibrium.
  4. 6.4

    Redox

    Oxidation and reduction in terms of oxygen and electrons, oxidising and reducing agents, and oxidation numbers.

    Full lesson1 questions4 cardsReview first: 4.1
    • 6.4.1Define oxidation and reduction in terms of oxygen loss/gain and electron loss/gain.
    • 6.4.2Identify oxidising and reducing agents in a redox reaction and use oxidation numbers.