The Maxwell-Boltzmann Distribution

What is the Maxwell-Boltzmann Distribution?

The Maxwell-Boltzmann Distribution

Points to notice

What is the Maxwell-Boltzmann Distribution?

All the molecules of a particular chemical, compound or element have the same mass, so their kinetic energy is only dependent on the speed of the particles.

Remember Kinetic Energy = ½mv2

In any particular mixture of moving molecules, the speed will vary a great deal, from very slow particles (low energy) to very fast particles (high energy). Most of the particles however will be moving at a speed very close to the average.

The Maxwell-Boltzmann distribution shows how the speeds (and hence the energies) of a mixture of moving particles varies at a particular temperature.

The Maxwell-Boltzmann Distribution

Points to notice:

  • No molecules at zero energy

  • Few molecules at high energy

  • No maximum energy value

For the reaction to occur, the particles involved need a minimum amount of energy - the Activation energy (EACT). If a particle is not in the shaded area, then it will not have the required energy so it will not be able to participate in the reaction.