3.1.5 Kinetics Flashcards
What is the collision theory?
Reactions can only occur when collisions take place between particles having sufficient energy (Activation energy)
Define Activation energy?
The minimum amount of kinetic energy that particles need to react is called the activation energy
Why don’t most collisions lead to a reaction?
This is because the two particles must have the right conditions:
- They need to be facing each other in the right way
- They need to collide with a minimum amount of kinetic energy
What is Maxwell-Boltzmann distribution curve?
A graph displaying the amount of molecules in a gas with different kinetic energies
What variable affects the Maxwell-Boltzmann distribution curve?
Temperature
Define rate of reaction
The change in concentration (or amount) of a reactant or product over time
Formula for rate of reaction
rate of reaction = amount of reactant used or product formed/time
What is the effect of changes of temperature on the rate of reaction?
Increasing temperature will lead to more successful collisions due to particles having more energy to collide
What is the effect of changes of concentration on collision frequency?
Increasing concentration will lead to more collisions as there will be more particles present
What is the effect of change in pressure of a gas on collision frequency?
Increasing pressure of a gas will lead to more collisions as particles are forced to be closer together
What is a catalyst?
A substance that increases the rate of reaction without being changed in chemical composition or amount
How do Catalysts increase rate of reaction?
By giving the reaction an alternative pathway of lower activation energy
