Question

What is Brownian motion? Explain its principle

Answer 1

Colloidal particles follow a zig-zag path. The random zig-zag motion of colloidal particles is called the Brownian Motion.
This motion can be observed in a dark room where a ray of sunlight enters the room through a small opening and in a film theatre where a beam of light which falls on the screen
shows zig-zag motion of particles.

Answer 2

Answer:

(1) Brownian movement : The random ceaseless motion of the colloidal or disperse phase particles taking place in all directions over a large area is called Brownian motion.

(2) Cause of Brownian motion :

(i) This movement arises due to constant bombardment by the molecules of the dispersion medium on the colloidal particles. colloidal particles acquire kinetic energy due to collisions by the dispersion medium molecules.

(ii) Since the colloidal particles are heavier than the molecules of the dispersion medium their Brownian motion is much slower than that of the medium molecules.