Topic 1.5 - Kinetics

What must particles do in

order to react?

Collide with sufficient energy (activation energy)

and the correct orientation

Do most collisions result in

a reaction?

no

Define Activation Energy.

The minimum energy that particles must collide

with for a reaction to occur

Draw a labelled Maxwell-Boltzman

Curve. Label average energy, activation

energy and most probable energy.

Draw in a different colour the effect of

increasing temperature

What is the effect of

increasing temperature on

rate of reaction? why?

Increasing temperature → increased rate of

reaction

Much higher proportion of particles have energy

greater than the activation energy → many more

successful collisions per second →increased rate

What is the effect of

increasing

concentration/pressure on

rate of reaction? why?

Increased concentration/pressure → increased rate of

reaction

There are more particles in a given volume → more frequent

successful collisions → increased rate

What is a catalyst?

A substance which increases the rate of reaction

but is not used up in the reaction

How do catalysts work and

how do they increase the

rate of reaction?

Provide an alternative reaction pathway (one with a lower

activation energy)

Lowers activation energy, so more particles have energy >

activation energy, so more frequent successful collisions, so

increased reaction rate