Maxwell Boltzmann Distribution. :D

Yea, in a bit they'll be a tonnnneeeee of unit one bio stuff on it's way for all yous retaking. But fo' nowwww...

A Maxwell-Boltzmann distribution curve expresses the 'energy' against the 'fractions of particles that have that energy', because in a solution all particles are moving at different speed, and, as speed and energy are relative to each other, there are varying energies.

It tells us that no particles have zero energy, and also, that as the curve peaks to the middle, intermidiate levels of energy is the most frequent. The right hand side of the graph is small, which means that not many have high energies.

With the Ea (Activation energy) marked on the graph, the area under the curve to the right of this, is the amount of particle with enough energy to overcome it. (And then like, react.)

Fuels are safe at room temperature, but a spark can provide energy for them to react. Match heads do not combust without friction. Nor lighters, come to think of it.

When a Maxwell-Boltzmann curve is affected by temperature, the curve shape changes. With higher temperatures, the curve gets shorter and fatter, and the amount of particles meeting the Ea increases. At lower temperatures, the curve gets taller and thinner, so like, nearer to the axis on the right? So, at high temperatures, more particles have equal or higher energy to the Ea, whereas at lower temperatures, less do.