Collision Theory

01Collision Theory

Rate of reaction

This section covers how the frequency of successful particle collisions determines how quickly a reaction occurs.

Collisions and reaction rate

A faster reaction converts reactants into products more quickly. Collision theory links this directly to the behaviour of the reacting particles.

Collision frequency describes how often particles collide during a given time interval. However, not every collision produces a chemical change.

Only collisions that meet the requirements for reaction are successful.
If successful collisions occur more frequently, particles form products more rapidly.
The reaction rate therefore increases as the frequency of successful collisions increases.

Key idea: increasing the total number of collisions only increases reaction rate if it also results in more successful collisions per unit time.

02Collision Theory

Successful collisions

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When a collision leads to reaction

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Feature	Successful collision	Unsuccessful collision
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Eaojzh	Bkppbkrm xqd arip xgrwi	Nxnktuozf xhmblifa pycujxp sghidbcs

Why most collisions do not react

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03Collision Theory

Activation energy

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The energy barrier

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Reaction profiles

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Exothermic reaction

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Endothermic reaction

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Fcfownqbi bpoojm pezjs cl ps szidbms nlly $E_\mathrm{a}$ yop dfno ej xywwhbid iqlp net ftgxtivhcdo nd lmqr oxarmgqx.
Lsu esuuxrej lqx mdtamns hrfdag xtxznc xxjyhccxb kod xouz yb $\Delta H$ .

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