Difference Wiki

Tyndall Effect vs. Brownian Motion: What's the Difference?

Edited by Janet White || By Harlon Moss || Updated on October 24, 2023
The Tyndall effect is the scattering of light by colloidal particles, while Brownian motion refers to the erratic movement of particles suspended in a fluid.

Key Differences

The Tyndall effect and Brownian motion are both phenomena related to the behavior of particles in a medium. The Tyndall effect is primarily concerned with the interaction between light and colloidal particles. When light passes through a colloid, the dispersed particles scatter the light, making the light path visible. This effect is particularly pronounced when the particles are of a size that is similar to the wavelength of the incident light.
Brownian motion, on the other hand, deals with the movement of particles. It refers to the random, erratic motion exhibited by particles when suspended in a fluid (liquid or gas). This movement is a result of the continuous collision between the suspended particles and the molecules of the fluid in which they are dispersed. It was named after Robert Brown, the botanist who first observed the phenomenon.
Interestingly, while the Tyndall effect is specifically associated with colloids, Brownian motion can be observed in both colloids and true solutions. This is because the Brownian motion results from molecular kinetic energy, irrespective of the size of the suspended particles.
In essence, while both the Tyndall effect and Brownian motion are related to the behavior of particles in a medium, they describe different phenomena. The Tyndall effect focuses on the scattering of light, while Brownian motion describes the random motion of particles due to molecular collisions.

Comparison Chart

Nature of Phenomenon

Light scattering
Random motion


Interaction of light with colloidal particles
Molecular collisions with suspended particles

Observed in

Colloids and true solutions

Associated Scientist

John Tyndall
Robert Brown

Related to

Size of particles relative to light wavelength
Kinetic energy of fluid molecules

Tyndall Effect and Brownian Motion Definitions

Tyndall Effect

A diagnostic tool for distinguishing between colloids and true solutions.
In the chemistry lab, students utilized the Tyndall effect to categorize their mixtures.

Brownian Motion

Named after botanist Robert Brown who first described it.
Observing suspended particles in water, Robert Brown identified the Brownian motion phenomenon.

Tyndall Effect

Light scattering due to particles similar in size to the wavelength of the light.
The blue color of the sky is partially due to the Tyndall effect.

Brownian Motion

Motion resulting from molecular collisions.
The visible Brownian motion in the smoke cell was a consequence of air molecule interactions.

Tyndall Effect

An effect showing the presence of colloidal particles.
To determine if it was a true solution or colloid, she observed for the Tyndall effect.

Brownian Motion

Microscopic evidence of kinetic molecular theory.
Brownian motion offers visual proof that molecules are always in motion.

Tyndall Effect

The phenomenon making the path of light visible in certain media.
The Tyndall effect was evident when the sunlight streamed through the dusty room.

Brownian Motion

Random, erratic movement of particles in a fluid.
Under the microscope, the pollen grains displayed Brownian motion in water.

Tyndall Effect

Scattering of light as it passes through a colloid.
The beam of a flashlight in fog displays the Tyndall effect.

Brownian Motion

A phenomenon observed in both colloids and true solutions.
Regardless of its colloid status, the suspended particles exhibited Brownian motion.


What type of light is best to observe the Tyndall effect?

A beam of visible light, like from a flashlight, is commonly used to observe the Tyndall effect.

What causes the Tyndall effect?

The Tyndall effect is caused by the scattering of light by colloidal particles.

What factors affect Brownian motion?

Temperature, size of the particles, and the viscosity of the medium influence Brownian motion.

Are the Tyndall effect and Brownian motion related?

light scattering vs. random particle motion.

Why is the Tyndall effect not observed in true solutions?

In true solutions, solute particles are too small to scatter light in a way that's observable as the Tyndall effect.

Can the Tyndall effect be used to determine particle size?

While the Tyndall effect can indicate the presence of colloidal-sized particles, specific particle sizing would require more advanced techniques.

Why is Brownian motion considered evidence for the kinetic molecular theory?

Brownian motion visually demonstrates the continuous movement of molecules due to their kinetic energy.

Is Brownian motion the result of the life force in cells?

No, Brownian motion is a physical phenomenon and not related to any life force.

Is the Tyndall effect only seen in liquids?

No, the Tyndall effect can be observed in both liquid and gaseous colloids.

Does the intensity of Brownian motion increase with particle size?

Smaller particles generally exhibit more pronounced Brownian motion due to their lighter mass and increased susceptibility to molecular collisions.

What practical applications arise from the study of Brownian motion?

Brownian motion has implications in various fields, including physics, chemistry, and finance, influencing areas like particle theory, stock market modeling, and more.

Can the Tyndall effect be observed in true solutions?

No, the Tyndall effect is specific to colloids.

Can the Tyndall effect be observed in the dark?

No, the Tyndall effect requires a light source to observe the scattering of light by particles.

How did Robert Brown come to observe Brownian motion?

Robert Brown observed the erratic movement of pollen grains in water under a microscope.

Does the Tyndall effect explain why the sky is blue?

Partially, the blue color of the sky results from scattering of sunlight, similar to the Tyndall effect.

Are there factors that can intensify or diminish the Tyndall effect?

Yes, factors such as particle size, concentration, and the wavelength of incident light can affect the intensity of the Tyndall effect.

Who discovered Brownian motion?

Brownian motion was first observed by botanist Robert Brown.

Is it possible to reduce Brownian motion?

Lowering the temperature can reduce Brownian motion as it decreases the kinetic energy of molecules.

Is the Tyndall effect responsible for the blue color of oceans?

While the Tyndall effect contributes to the blue of oceans, other factors like water absorption and reflection also play roles.

Can Brownian motion be observed with the naked eye?

Typically, Brownian motion is observed microscopically due to the small size of the particles. However, in some cases with larger particles or with phenomena like smoke particles in the air, it may be noticeable without magnification.
About Author
Written by
Harlon Moss
Harlon is a seasoned quality moderator and accomplished content writer for Difference Wiki. An alumnus of the prestigious University of California, he earned his degree in Computer Science. Leveraging his academic background, Harlon brings a meticulous and informed perspective to his work, ensuring content accuracy and excellence.
Edited by
Janet White
Janet White has been an esteemed writer and blogger for Difference Wiki. Holding a Master's degree in Science and Medical Journalism from the prestigious Boston University, she has consistently demonstrated her expertise and passion for her field. When she's not immersed in her work, Janet relishes her time exercising, delving into a good book, and cherishing moments with friends and family.

Trending Comparisons

Popular Comparisons

New Comparisons