Boltzmann distribution Flashcards
Where must the Boltzmann distribution curve start?
At the origin
What does the peak represent?
The modal energy (the energy of the largest number of particles)
At high energy what happens to the curve?
It becomes asymptotic
What does the area under the curve represent?
The total no. Particles in the system
What does the area under the curve greater than the activation energy represent?
The molecules which can react
In terms of what will happen when they collide, what is true of most particles in any sample?
Collisions between most molecules in a sample do not lead to a reaction
State two things that happen to the peak of the curve when the temperature is raised
The modal energy is higher
The no. particles with modal energy is lower
What is the x axis of the Boltzmann distribution?
Kinetic energy
What is the y axis of the Boltzmann distribution?
No. Particles
What happens to the total area under the curve if the temperature is increased?
It remains the same
What happens to the high energy part of the curve if temperature is increased?
A higher proportion of particles have the higher energy, it moves away from the energy axis
Give two reasons why an increase in the temperature causes the rate of reaction to increase
- No. particles with energy exceeding that of the Ea is greater
- Frequency of collisions increases
What happens to the proportion of molecules which possess at least the activation energy in the presence of a catalyst?
The proportion of molecules increases
Give two reasons why the presence of a catalyst causes the rate of a reaction to increase
- provides an alternative route to the reaction
- more particles react with the required activation energy or more