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Describe the key concepts of collision theory, including particle density, collision frequency, kinetic energy, and activation energy.

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Cambridge IGCSE Combined ScienceChemical reactionsSupplement content

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Describe the key concepts of collision theory, including particle density, collision frequency, kinetic energy, and activation energy

This point belongs to Rate of reaction, especially Rate of reaction outcomes.
You need to be able to describe the key concepts of collision theory, including particle density, collision frequency, kinetic energy, and activation energy.
The key ideas to know are Describe, Define, and Explain.
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Key concepts

DescribeDefineExplain

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Paper 4 structured question: Rate of reaction

Paper 4Theory (Extended)3 marks

Description

Collision Theory Concepts

Collision theory explains how chemical reactions occur based on particle interactions. Key concepts include particle density, collision frequency, kinetic energy, and activation energy.

a
Explain the role of activation energy in chemical reactions.
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Aim for approximately 3 distinct marking points.
[3]

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Related learning objectives

Explain how the rate of a reaction is influenced by factors such as the concentration of solutions, the surface area of solids, the temperature, and the presence of a catalyst.
Rate of reaction outcomes
Recognize that a catalyst speeds up a reaction and remains unchanged after the reaction is complete.
Rate of reaction outcomes
Outline methods for conducting experiments to measure the rate of a reaction, including observing changes in mass or gas production.
Rate of reaction outcomes
Analyze data from experiments on the rate of reaction, including interpreting graphs.
Rate of reaction outcomes
Discuss how factors such as concentration, surface area, temperature, and catalysts affect the rate of reaction through the principles of collision theory.
Rate of reaction outcomes

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