Why does increased concentration increase rate of reaction?
More likely for particles with high enough Ea to have successful collisionsper second, resulting in higher likelihood of reaction occurring
Why does increased surface area increase rate of reaction?
Increasing surface area increases the likelihood of successfulcollisions per second, which increases likelihood of reaction occurring
Why does increased temperature increase rate of reaction?
The particles will have increased kinetic energy, therefore more particles will have the required activation energy
Why does increased pressure increase rate of reaction? ONLY FOR GASES
The particles will be in a smaller volume, therefore more successful collisions with the necessaryEa will occur, therefore reaction rate will be increased
What is a catalyst?
Increases reaction rate without being used up by offering alternative route with lower activation energy
Why is a catalyst used?
-To provide a pathway with lower activation energy or provide a surface for the reactant to take place on
What is a homogenous catalyst?
A catalyst in the same phase as the reactants
What is a heterogenous catalyst?
A catalyst in a different phase as the reactants
What is beneficial about using a catalyst?
It reduces temperature required to start non-spontaneous reactions
-More economically viable than increasing temp/ pressure which uses more fuel
Maxwell-Boltzmann distribution
Shows the distribution of energies that molecules of gas or liquid have at a particular temperature
Features of a Maxwell-Boltzmann distribution
- No molecules have zero energy - the curve starts at the origin
- The area under the curve is equal to the total number of molecules
- There is no maximum energy for a molecule - the curve does not meet the x-axis at high energy
How does Boltzmann distribution change with temperature?
Higher temperature - Probable speed point shifts right and lower down as more particles are more likely to have Ea
How does Boltzmann distribution change with catalysts?
Graph itself does not change - Activation energy
What is dynamic equilibrium?
Where the rate of the forward reaction and the rate of the backward reaction are equal in a closed system
What is important about the concentration of reactants and products in a closed system?
They do not change
What is Le Chatelier's principle?
When changes are made to a system, the system will oppose them
What happens when temperature is increased in a closed system?
The reaction will shift in the endothermic direction
What happens when pressure is increased in a closed system?
The side with less moles is favoured
What happens when concentration of product is increased?
The reactant is favoured
How do catalysts act in dynamic equilibria?
They increase the rate of reaction of both the forward and backward reaction equally, resulting in an unchanged position of equilibrium
What are compromise conditions?
Conditions that maximise yield of product with the most economically viable conditions