chem Topic 6 kinetics

1. Particles colliding must have kinetic energies equal to or grater than the reaction’s activation energy.

2. The particle must collide with the correct geometry/orientation

The activation energy is defined as the minimum value of kinetic energy which particles must have to react.

It represents an “energy barrier” for the reaction.

• Temperature (only one that does it in 2 ways)

• Catalyst

• Conentration

• Surface area (particle size)

• Pressure (reactions involving gases)

They provide an alternate reaction pathway that has a lower activation energy.

• Catalysts increase the number and proportion of particles that have sufficient energy to meet or exceed activation energy.

• ∴ increase freuency and proportion of successful collisions

• ∴ increase ROR

• Increasing the temperature increases the proportion of reactant particles with sufficient energy to meet or exceed the reactions activation energy. As well as increases the average random kinetic energy of particles.

• ∴ increase freuency and proportion of successful collisions

• ∴ increase ROR

• As concentration increases there are more particles available to react in a given volume.

• ∴ increase freuency of successful collisions

• ∴ increase ROR

• decreasing particle size increases total surface area

• ∴ increase in number of particles available to react

• ∴increase in number and frequency of successful collisions

• ∴ increase ROR

• as pressure increases the gas is compressed and so the concentration increases.

• As concentration increases there are more particles available to react.

• ∴ increase freuency of successful collisions

• ∴ increase ROR

• equal redutoin in the activation energy of both forward and backwards reactions

• hump is lowered

is expressed by change in concentration of a particular reactant/product per unit time

this can be indirectly observed through changes in mass, volume and color.

less frequency/chance of collisions as reaction proceeds