At any given temperature, molecules have a range of speeds and energies. The distribution of speeds and energies can be shown by the Boltzmann distribution curve.No molecules have zero energy so the curve starts at the origin.Most molecules move close to the average speed and have close to the average energy.Only a small proportion of molecules have energies above the activation energy.The area under the curve is equal to the total number of molecules.There is no maximum energy for a molecule. The curve does not meet the x-axis on the right.At a higher temperature the peak is lower and to the right. More molecules have and energy equal to or greater than the activation energy so collisions will be more frequent and more collisions will result in reactions taking place.