What is Tyndall effect? Describe an activity to show that a true solution does not show Tyndall effect

Tyndall effect is the process of scattering of a beam of light by the dispersed phase of a colloidal solution.

Explanation:

This only takes place in such a solution where the particles have size b/w 1000nm to 1 nm. these particles keep floating because they have charge as well as they too light to sink, thus they are not affected even on the acting of gravitational force. this is therefore only possible in a colloidal solution and sometimes even in suspension as particles are first seen floating then on gravity they settle down. To show this we can perform a small activity,

We need to take two solutions - a true solution like salt water and a colloidal solution like milk solution.

using a torch pass a beam of light through the solutions. you will notice that in the case of a milk solution, you can see the path of light as the dispersed phase particles reflect it. but in the case of a true solution it is unable to see the path of light as the particles are too small. The path of light therefore cannot be seen.

Hence, this proves that true solution cannot show Tyndall effect whereas colloidal solutions show.

The Tyndall effect is the scattering of light as a light beam passes through a colloid. The individual suspension particles scatter and reflect light, making the beam visible. The amount of scattering depends on the frequency of the light and density of the particles

Explanation:

And an activity to see if the solution doesn't show the tyndall effect is to try to shine a flaslight through it and see if you can see it coming out the other end