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Question
Write a note on Brownian motion.
Solution
- The colloidal or microscopic particles undergo ceaseless random zig-zag motion in all directions in a fluid. This motion of dispersed phase particles is called Brownian motion.
- Cause of Brownian motion:
- Particles of the dispersed phase constantly collide with the fast-moving molecules of the dispersion medium (fluid).
- Due to this, the dispersed phase particles acquire kinetic energy from the molecules of the dispersion medium.
- This kinetic energy brings about Brownian motion.
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