Which of the following phenomena is the practical evidence for the existence of the continual motion of molecules.

A. Transitional Motion
B. Rotational Motion
C. Brownian Motion
D. Oscillatory Motion

Correct Answer:

Option C – Brownian Motion

Explanation

Brownian motion, also called Brownian movement, any of various physical phenomena in which some quantity is constantly undergoing small, random fluctuations.

If a number of particles subject to Brownian motion are present in a given medium and there is no preferred direction for the random oscillations, then over a period of time the particles will tend to be spread evenly throughout the medium.