10.3 - Boltzmann Distribution Flashcards
What is the Boltzmann distribution?
The spread of molecular energies in gases.
Why are collisions of gas molecules said to be elastic?
The molecules do not slow down as a result of a collision and no energy is lost.
What does the line on a Boltzmann graph represent?
Activation energy
Why does the line on a Boltzmann distribution graph start at the origin?
No molecules have zero energy
What is the area under the curve of a Boltzmann distribution graph equal to?
The total number of molecules
Why does the curve not meet the x-axis in a Boltzmann distribution graph?
There is no maximum energy for a molecule
What are the x and y axis in a Boltzmann distribution graph?
x-axis = energy
y-axis = number of molecules with given energy
Describe how a Boltzmann distribution graph changes at a higher temperature
At a higher temperature:
- More molecules have activation energy or higher
- The average energy of molecules increases
- A small proportion of molecules will still have low energy but most have higher energy
- The graph is stretched out over greater range of values, and the peak is at a higher energy
- The number of molecules is the same so the area of the curve remains the same
What happens to the Ea when a catalyst is added to the reaction?
Ea is lowered.
More molecules now have Ea or above.
