Question

state the difference of the colour of the sun observed during sunrise /sunset and noon. Give reason for each

Answer 1

the time of sunrise and sunset the sun appears reddish in colour.
at noon  the sun appears white in colour. these are due to scattering of light. at noon the sun appears white as only a little of blue and violet colours are scattering. at the time of sunrise and sunset the sun is near the horizone then the blue light of shotter wavelength are scattered away thus it give rise to reddish appearane

Answer 2

Sun appears red at sunrise and sunset : At sinrise and sunset, sun is closer to the horizon. The sunlight passes through denser layer of air and covers larger distance before reaching our eyes. Most of the blue light gets scattered. The light that reaches our red. That is why the sun appears red at sunrise. 

At noon, the sun is overhead. The sunlight passes through rares layers of air and covers shorter distance before reaching our eye. So, almost all colours of light are scattered equally. Hence the sun appears white