15-The Boltzmann Factor Flashcards
What is the mean energy per particle in an ideal gas?
3 / 2 kT
As we only need an order of magnitude for the energy, what do we approximate mean particle energy to be?
kT
What equation relates energy and plack’s constant?
E=hf
What are extremely low energies represented as?
Electron volts
What does 1ev equal?
1.6 X 10-19
What is the activation energy?
The certain amount of energy required for a reaction to take place
In chemistry, why do we have to heat reagents in order for them to react?
So that the reagents can gain enough kinetic energy in order to react
What does water need in order to evaporate?
Thermal energy
Why can nuclear fission occur in centre of the sun?
Because of the temperature of many million kelvin there
What is the variation of resistance with temperature in thermistors due to?
The thermal ionisation of atoms in the semiconductor lattice
What is the Boltzmann ratio?
E / KT
How do your clothes dry?
- Water molecules on the clothes have a range of different energies
- Some will have enough energy to escape from the surface
- When they do the mean energy of the water molecules will drop
- The newly cooled water will gain energy by collision with other particles in the warmer environment, giving more water molecules enough energy to escape
If E / kT for the energy needed to liberate one water molecule from a liquid is 16, what does this suggest?
The energy needed to liberate 1 one water molecule from the liquid is 16 times greater than the available energy per particle at room temp
What value of E / kT will a reaction occur at an appreciable rate?
15kT - 30kT
If the value of E / kT is below 15, what does this mean?
The rate would be extremely fast
