Difference WikiChemistry

Difference Between Tyndall Effect and Brownian Motion

Main Difference

The main difference between the Tyndall Effect and Brownian Motion is that the Tyndall Effect is the light scattering phenomenon in a colloidal substance, whereas Brownian Motion is due to collisions of particles by their random motion.

Tyndall Effect vs. Brownian Motion

Tyndall effect was given by the Irish Physicist John Tyndall in the 19th century whereas, Brownian motion was given by the Scottish botanist Robert Brown in 1827. Tyndall effect is the light scattering phenomenon that is affected by the various sized substances, while Brownian motion is the collision of particles of substance with different atoms or molecules of fluids by their random movement. Tyndall effect is observable in the media such as colloidal solutions which are heterogeneous mixtures, on the flip side of the coin, Brownian motion is observable in the fluids whose atoms or molecules are in the state of continuous motion.

ADVERTISEMENT

Tyndall effect is affected by the wavelengths of light, such as longer wavelengths are less scattered by the colloids as well as the frequency of falling light and density of the colloidal substance. Brownian motion is affected by factors such as the concentration of molecules, temperature, viscosity, and size of particles. Tyndall effect applied on the colloid solutions have substances of diameter 40 to 900nm, whereas, Brownian motion applied efficiently on the small diameter molecules experience less friction.

The Tyndall effect can be observed with the human eye by passing a light beam through the colloidal substance, whereas a light microscope is used to observe the Brownian motion of particles as random motion. Examples of Tyndall effect are the glass of dilute milk on which when the flashlight is used, scattering is observed, and blue light of eye as well. Examples of Brownian motion are the diffusion of dust particles and gases from the industries in the air and calcium diffusion from the blood in bones.

ADVERTISEMENT

Comparison Chart

Tyndall EffectBrownian Motion
Tyndall effect is the light scattering phenomenon by different wavelengths of light on the colloidal solution.Brownian motion is the collision of molecules or atoms of fluid by the random movement of particles of fluid, which are in the state of continuous motion.
Observation Medium
By Human eyeBy light microscope
Concept
Light scattering phenomenonMovement of particles by collisions
Applicable Medium
Colloidal solutionsFluids such as liquids, gases.
Size of Substance
From 40 to 900nmSmaller diameter
Factors Affecting
Wavelengths of light, the density of a colloidal substance, frequency of lightSize of particles, temperature, viscosity, the concentration of particles
Examples
Milk solution, Soap solutions, Opalescent glassDiffusion of dust, gases in the air, Diffusion of calcium to bones
ADVERTISEMENT

What is the Tyndall Effect?

It works based on principle showing the scattering of light by different wavelengths on the substances of various sizes.

Tyndall Effect, as a light scattering phenomenon, was first observed by the Irish Physicist named John Tyndall in the 19th century. This phenomenon applies to colloidal solutions that are not fine and are heterogeneous mixtures having particles of diameter 40 to 900nm. In this effect, light is scattered, which may vary by the factors of the frequency of light and density of colloid substance on which light is falling. Tyndall effect is characteristic of colloidal solutions which distinguish them from the true solutions.

Longer wavelengths of light, such as red light, are resistant to scattering as it is transmitted out through the colloidal solution, but shorter wavelengths of light such as blue light show a higher scattering effect. Blue light shows the Tyndall effect of scattering ten times more than the red light.

Applications

  • The Tyndall effect can be observed in the milk glass by diluting it with the water and then falling flashlight beam on it. It shows the colloidal particles being affected by the light.
  • For the determination of aerosol’s particle size, the Tyndall effect is used in the laboratory.
  • In the fog, water droplets are present, which are responsible for making the headlights visible by scattering the light.
  • Opalescent glass displays the light as orange when it shines through it whereas, its actual color is blue. Soap solutions, starch, albumin, blood are also examples of Tyndall effects shown by colloids.

What is the Brownian Motion?

As a diffusion, Brownian motion is the collision of particles with atoms or molecules by their random motion in a fluid, which may be liquid or gas.

Brownian motion was first observed in 1827 in the pollens of plant Clarkia pulchella, which were immersed in the water(fluid) moving by collisions with molecules of water by the Scotland botanist named Robert Brown; therefore, it is called Brownian motion. It is also named as pedesis originated from the Greek word, which means leaping. It is also taken into consideration as the terms Gaussian process as well as the Markov process.

Brownian motion as a macroscopic property is affected by the microscopic effects of random movements of atoms or molecules. Various factors may affect by direct relation, increasing the rate of Brownian motion.

Examples are the diffusion of pollutant gases and fluids in air, calcium diffusion in bones from the blood, holes movement in semiconductors of electrical charge, pollen grains moving in the still water by collision with molecules or atoms of water which are in a state of continuous motion.

Factors Affecting the Brownian Motion

  • In Diffusion, the region of the higher number of particles allows the particles to diffuse to the region of less number of particles.
  • Small-Sized Particles faceless frictional force in motion hence moved freely.
  • Low Viscosity is favorable to an increased rate of Brownian motion.
  • High Temperature increases the kinetic energy of molecules, which leads them to a higher rate of Brownian motion.

Key Differences

  1. Tyndall effect is the phenomenon of light scattering by the colloidal particles as they are big enough to scatter the light; on the other hand, Brownian motion is the motion of particles of a substance by collisions with fluid molecules.
  2. The Tyndall effect involves the scattering of light, whereas Brownian motion involves the collision of particles.
  3. Tyndall effect is named after the John Tyndall discovery in the 19th century; conversely, Brownian motion is named after the scientist Robert Brown in 1827.
  4. Tyndall effect occurs in the colloidal solutions whose particle sizes are larger; on the flip side of the coin, Brownian motion occurs in fluids such as liquids and gases whose molecules are in the state of motion.
  5. Tyndall effect is macroscopic property results from the microscopic effects of particles of colloids, while Brownian motion is also a macroscopic property influenced by the microscopic effects of the molecules.
  6. The Tyndall effect is affected by the frequency, wavelength of light, and density of colloidal solutions; on the flip side, Brownian motion is affected by the size, concentration of particles, viscosity, and temperature.
  7. Tyndall effect can be observed by the human eye as in milk solutions, while Brownian motion can be observed by light microscope as pollen grains in still water.

Conclusion

Tyndall effect explains the scattering of light by the colloidal solutions of different sizes, whereas Brownian motion deals with the motion of particles by collision with fluid molecules.

Harlon Moss

Harlon currently works as a quality moderator and content writer for Difference Wiki. He graduated from the University of California in 2010 with a degree in Computer Science. Follow him on Twitter @HarlonMoss