Rate of Reaction - Collision Theory & Factors

factors that affect rate of reaction

1) temperature

2) concentration/pressure

3) surface area

4) catalyst

what is collision theory

a criteria for particles in order to react

collision theory criterias

1) particles have to collide

2) particles have to collide with correct orientation

3) particles must have at least the minimum required energy (activation energy)

temperature

1) temp increases —> heat energy turn into kinetic energy

2) particles have more activation energy to move —> and so they move faster

3) moving faster —> they collide more

4) more collisions = more frequent successful collisions

5) rate increases

concentration

1) increase concentration = increase no.particles in set volume

2) more particles in same place = more collisions

3) more frequent collisions = more frequent successful collisions

4) rate increases

pressure

1) increase pressure = same number of particles in a smaller volume

2) particles are closer together = more collisions

3) more frequent collisions = more frequent successful collisions

4) rate increases

what happens if you double the concentration?

double concentration = doubles the no.collisions and therefore the rate of reaction doubles

surface area

1) increase in surface area = smaller particles used

2) smaller particles = have more energy = move faster

3) increase in surface area = more collisions at surface

4) more collisions = more frequent and effective collisions

5) faster rate

catalysts

1) catalysts = reduce activation energy needed for reaction —> they offer alternative route for reaction to take

2) less activation energy = more frequent and effective collisions

3) more frequent and effective collisions = faster rate