CHEMISTRY GLOSSARY

When a light ray comes on a boundary between two transparent media, it will be partly reflected and partly refracted. Both rays, reflected and refracted ray, lay in the plane of incidence. The angle of reflection is equal to the angle of incidence. The angle of refraction (Θ₂) is related to the angle of incidence (Θ₁) via Snell’s law:

where n₁ and n₂ are dimensionless constants - indexes of refraction of the two media.