Answer the question on the basis of passage given below:

A colloid is a heterogenous system in which a substance is dispersed (dispersed phase) as fine particles in another substance called dispersion medium. Their particle size is intermediate between that of pure solutions (<1 nm) and suspension (>1000 nm).

They are known for interesting properties such as enormous surface area, Tyndall effect, Brownian Motion etc. They are widely used in industries and day to day life. Some prominent uses of colloids are those in smoke precipitators, purification of water, medicines cleansers etc.

Which of the following statement is false regarding charge on sol particles?

Scattering of light by colloidal particles.

The correct answer is Option (2) → Scattering of light by colloidal particles.

The false statement regarding the charge on sol particles is: Scattering of light by colloidal particles.

Let us analyze each statement:

1. Electron capture by sol particles:

This is true. Sol particles can acquire a charge by capturing electrons from the surrounding medium. This contributes to the overall charge on the particles.

2. Scattering of light by colloidal particles:

This is false in the context of the charge on sol particles. Scattering of light by colloidal particles (Tyndall effect) is a property of colloids, but it does not relate to the charge on sol particles. The Tyndall effect explains the visibility of colloids, not the mechanism behind their charge.

3. Preferential adsorption of ions from solution:

This is true. Colloidal particles often develop charge by preferential adsorption of certain ions from the surrounding solution. For example, if a sol particle adsorbs negative ions, it will become negatively charged.

4. Due to formation of electrical double layer:

This is true. The charge on colloidal particles can also arise due to the formation of an electrical double layer, where one layer of ions is adsorbed onto the particle and another layer is loosely associated around it, forming a charged particle.

Conclusion

The false statement is "Scattering of light by colloidal particles." While scattering is an important property of colloids, it does not explain the charge on sol particle