Collision theory syays that a reaction won't take place between two particles unless they collide in the right direction and they collide with at least a certain minimum amount of kinetic energy
The minimum amount of kinetic energy particles need to react is called the activation energy. This much energy is needed to break the bonds within the reactant to start the reaction.
Increase temperature means particles increase in kinetic energy so...
they are moving faster and will collide more often leading to a higher frequency of successful collisions
greater proportion of molecules will have at least the activation energy leading to an increased frequency of successful collisions
The Maxwell-Boltzmann distribution curve pushes over to the right but the area under the curve stays the same so the mode will be lower
Increasing concentration/pressure:
more particles per unit volume/reduces volume
molecules collide more often
higher frequency of successful collisions
A catalyst increases the rate of a reaction by providing an alternative reaction pathway with a lower activation energy meaning there are more particles with enough energy to react when they collide.
The catalyst is chemically unchanged at the end of the reaction meaning you only need a tiny bit to catalyse a huge amount of stuff.
Maxwell-Boltzmann distribution curve is unchanged.
