The scattering of light is the occurrence of light bouncing off the molecules of the material through which it is propagating in a random path.
Scattering of light depends upon the size of the particle and the wavelength of light which interacts, the greater the wavelength lesser the scattering. Blue light is scattered more than red (Blue has a lesser wavelength) in the sky is an example of the scattering of light. Another example is the red sky after the sunset.
Red light has a wavelength greater than blue light, so it can travel long distances without interacting with particles or without any scattering. So we see the sky as red during sunset.
The below figure shows an image of a sunset.
Dispersion:
Dispersion is the phenomenon of splitting light into its constitute colors.
When light passes through a prism white light split into its spectrum of colors can be called dispersion.
In the diagram, you can see that white light has been split into different colors when coming out of the prims.
The below diagram shows the dispersion of light when light passes through a prism.