volume_mute

Microscopic Cause of Diffusion

publish date: 2026/05/19 08:39:31.712484 UTC

volume_mute

What is the primary microscopic mechanism that drives the process of diffusion in both liquids and gases?

The continuous, random thermal motion of individual molecules colliding with one another.

The gravitational forces drawing heavier molecules toward areas of lower elevation.

The presence of macroscopic convection currents stirring the bulk fluid.

Electrostatic repulsion between particles of identical atomic mass.

Correct Answer

The continuous, random thermal motion of individual molecules colliding with one another.

Explanation

Diffusion is a spontaneous transport process driven at the molecular scale by kinetic energy. Individual molecules are in a state of continuous, randomized thermal motion, constantly colliding and bouncing off one another, which naturally causes them to spread out over time.

Reference

Basic Physics: A Self-Teaching Guide

Quizzes you can take where this question appears

Diffusion through liquids and gases