1.5.1

Collision Theory

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Collision Theory

Collision theory is the theory of how reactions happen.

Illustrative background for When will a reaction happen?Illustrative background for When will a reaction happen? ?? "content

When will a reaction happen?

  • For a reaction between two molecules to happen, they must come into close proximity with each other.
  • For a particular reaction to happen, several conditions must be met:
    • The correct part of the molecules must collide.
    • The molecules must collide with enough energy to react.
Illustrative background for Steric factorIllustrative background for Steric factor ?? "content

Steric factor

  • The steric factor is the fancy name for saying that the location of a collision matters.
  • For example, if you were trying to react the OH bond in ethanol (CH3CH2OH), a collision with the CH3 group wouldn't do anything.
Illustrative background for Activation energyIllustrative background for Activation energy ?? "content

Activation energy

  • The activation energy is the energy needed for a reaction to happen.
    • The activation energy is used to break the bonds in the reactants before new bonds can form in the products.
  • For both reasons of activation energy and steric factor, most collisions do not result in a reaction.

Jump to other topics

1Physical Chemistry

2Physical Chemistry 2 (A2 Only)

3Inorganic Chemistry

4Inorganic Chemistry 2 (A2 Only)

5Organic Chemistry 1

6Organic Chemistry 2 (A2 Only)

6.1Optical Isomerism (A2 Only)

6.2Aldehydes & Ketones (A2 Only)

6.3Carboxylic Acids & Esters (A2 Only)

6.4Aromatic Chemistry (A2 Only)

6.5Amines (A2 Only)

6.6Polymers (A2 Only)

6.7Biological Organic (A2 Only)

6.8Organic Synthesis (A2 Only)

6.9NMR Spectroscopy (A2 Only)

6.10Chromatography (A2 Only)

6.11A-A* (AO3/4) - Organic 2

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