Question

Which of the follwing statement(s) is/are true ?

• A. Colloidal solution does not show Tyndall effect
• B. Colloidal solution show brownian movement
• C. Colloidal solution are heterogeneous in nature
• D. Size of the colloidal particles is less that $1nm$

Answer 1

Answer: (B), (C)

Colloidal solution are heterogeneous in nature

Tyndall effect and Brownian movement are properties of colloidal solutions.

Tyndall effect:
If a strong beam of ​light is passed​ through a colloidal sols placed in dark place,​ path of the beam ​gets illuminated. This effect is called Tyndall effect.
This effect was first observed ​by faraday later studied in ​detail by Tyndall​.
This effect arises due to scattering of light by colloidal​ particles in all directions . Thus, scattering of light illuminates the path of beam in the colloidal dispersion​.

Brownian movement:
Under ultramicroscope colloidal particles appear t​o be in a continuous ​zig-zag motion​ known as Brownian movement.

Colloidal solution are heterogeneous. They have two phase system, dispersed phase and dispersion medium, there is a definite surface of seperation between each particle of dispersed phase and the dispersion medium.

Size of the colloidal partical particle is between $1nm$ and $1000nm$.

Thus, statements (b) and (c) are correct.