Scattering and Absorption of Light

Interactions of Light with Solutions and Suspensions - Apparatus	The equipment and methods used to study what happens to light when it passes through solutions and suspensions are described.
Interactions of Light with Solutions and Suspensions - Spectral Changes	A diffraction grating can be used to study how light that has passed through a colloidal suspension or solution is altered.
Scattering of Blue Light and Red Light	Blue light is scattered more efficiently than red light. As we shall see, this explains why skim milk and the sky overhead are blue, but sunsets are red.
Light Scattering	When a few drops of milk are stirred into water, light is scattered and polarized.
Why the Sky is Blue and Sunsets are Red	Adding milk increases the amount of light scattered.
Spectrum of Transmitted Light	A diffraction grating is used to show the spectrum of the light that is not scattered by the milk suspension.
Light Absorption by a Solution	When a colored solution is placed in the path of a beam of white light, the light that passes through is the same color as the solution. With a solution there is almost no scattering of the light beam.
Why is a blue solution blue?	A blue solution transmits blue light, but absorbs light of other colors.

The effects of passing light through a colloidal suspension of milk in water and through a solution of copper sulfate are shown.