The sun is seen before the actual sun rise because of:ReflectionRefractionScattering of lightDispersion of white light

The sun is seen before the actual sunrise primarily due to the phenomenon of atmospheric refraction. Here's a step-by-step explanation:

1. Light from the sun reaches the Earth's atmosphere before the sun is actually visible to us.
2. As this light enters the Earth's atmosphere, it gets refracted, or bent, due to the change in medium (from vacuum to the Earth's atmosphere).
3. The Earth's atmosphere is denser closer to the surface, causing the light to bend more as it gets closer to the surface.
4. This bending of light causes the sun to appear higher in the sky than it actually is.
5. Therefore, we see the sun before it has actually risen above the horizon.

While scattering and dispersion also occur, they are responsible for the colors of the sunrise and sunset, not the early appearance of the sun.