Ozone: Rates of Reaction Flashcards
Definition of reaction rate
Change in concentration of a reactant or product per unit time
Definition of activation energy
Minimum energy particles need to react
What is the collision theory
- for particles to react they must collide with sufficient energy to react and at the correct orientation
- Minimum energy particles need to react is called the activation energy
How does increasing the concentration affect the rate of reaction
The higher the concentration the faster the reaction ( unless that reagent is 0 order )
Why does increase in concentration increase the rate of reaction
Particles are closer together so there are more frequent successful collisions
How does increasing the SA of a solid affect the rate of reaction
The greater the surface area the faster the reaction
The more pieces are solid is broken up into the greater the surface area e.g. a powder has a massive surface area
Why does increase in SA increase the rate of reaction
There are more particles exposed at the surface that can be collided with so there are more frequent successful collisions
How does increasing the pressure affect the rate of reaction
The higher the pressure the faster the reaction ( unless that reagent is 0 order )
Why does increase in pressure increase the rate of reaction
Particles are closer together and so there are more frequent successful collisions
How does increasing the temperature affect the rate of reaction
The higher the temperature the faster the reaction
Why does increase in temperature increase the rate of reaction
- Particles have more energy = greater proportion of the collisions are successful
- particles also move faster = collisions are more frequent
- therefore there are more frequent successful collisions
Definition of a catalyst
- substance that increases the rate of a reaction but is not used up
- provides an alternative route with a lower activation energy
= a greater proportion of the collisions are successful
How do you work out the rate of a reaction from a graph
Gradient of the tangent to the curve
Gradient = change in y / change in x
Be able to draw fully labelled Maxwell-Boltzmann distribution
For 1. Temp
2. Catalyst
Look at sheet
What is on the Y axes and X axes of a Maxwell Boltzmann distribution
Y axis = number of molecules
X axis = energy
