CHEM 103 Chapter Notes - Chapter M7Q2: Diffuse Sky Radiation, Skimmed Milk, Scattering
Document Summary
The short answer is that milk is white because it reflects all wavelengths of visible light. The mixture of reflected colors produces white light. The reason for this is due to the chemical composition of milk and the size of the particles contained within it. Milk is about 87% water and 13% solids. It contains several molecules that don"t absorb color, including the protein casein, calcium complexes, and fats. Although there are colored compounds in milk, they are not present in a high enough concentration to matter. The light scattering from the particles that make milk a colloid prevent much color absorption. Light scattering also accounts for why snow is white. The ivory or slight yellow color of some milk has two causes. First, the vitamin riboflavin in milk has a greenish yellow color. A diet high in carotene (the pigment found in carrots and pumpkins) colors milk.
