Three beams of white light passing through a colloid of sulphur particles in water change from orange to pink and blush green because the colour of colloidal solution depends on the

Options

A. wavelength of light scattered by the dispersed particles.
B. size of the colloidal particles
C. position of viewers
D. all of these

Answer

D

Explanation

The colour of colloidal solution depends on the wavelength of light scattered by the dispersed particles. The wavelength of light further depends on the size and nature of the particles. The smaller the particles, the shorter (bluer) the wavelength.
The colour of colloidal solution also changes with the manner in which the observer receive the light. For example, a mixture of milk and water appears blue when viewed by the reflected light and red when viewed by the transmitted light. Finest gold sol is red in colour but as the size of particles increase, it appears purple, then blue and finally golden.