The Tyndall effect 11) A) is caused by Brownian motion. B) is used to determine the osmotic pressure of solutions. C) is observed only in dilute solutions. D) is observed in concentrated solutions. E) is observed in colloidal dispersions.

E) is observed in colloidal dispersions  

Explanation:

The Tyndall effect is the scattering of light as it passes through a colloidal dispersion. The dispersed particles scatter and reflect the light and make the beam visible.

A) is wrong. Brownian motion is the random movement of particles in a fluid due to their collisions with molecules of the fluid. The particles must be visible, so they are larger than colloidal particles (> 1000 nm).

(B) is wrong. Osmotic pressure is measured by determining the pressure developed across a semipermeable membrane.

C) and D) are wrong. The solute particles in a solution are too small (< 1 nm) to scatter light