Collision theory

What things are required for a reaction according to collision theory

A collision, meeting the energy requirement, meeting the steric requirement.

Collision Cross-Section

Imagine all but one molecule is held still and this molecule moves in a straight line.

How is collision frequency, z, calculated

How do you calculate collision density, Z and how is it different

Taking the calculation from the previous slide and multiplying by the number density of A allows you to take all molecules of A into account at once. Number density includes the collisions of every molecule of A

How do you relate number density to concentration

little n is number of moles as usual

How can we calculate collision density using concentrations of different molecules

What is the Mean Free Path Length and how is it calculated

Maxwell-Boltzmann Distribution of Speeds

Effect of mass and temperature on the distribution

Equations to remember: Mean speed

Mean relative speed equation

Most probable speed

Root mean square speed

Energy distribution

Steric requirement component

How can the cross section be modified to account for steric requirements

The Harpoon Mechanism - an exception with sterics

How can the overall rate equation be expressed

How can this equation give us the Arrhenius equation

Limitations of collision theory