Question

Which one of the following statements is correct?

• A. Brownian movement is more pronounced for smaller particles than for bigger ones
• B. Sols of metal sulphides are lyophilic
• C. Schulze-Hardy law states, the bigger the size of the ion, the greater is its coagulating power
• D. None of these

Answer 1

Answer: (A)

Brownian movement is more pronounced for smaller particles than for bigger ones

Smaller the size and lesser the viscosity, the faster is the motion. Brownian movement arises because of the impact of the molecules of the dispersion medium with the colloidal particles.

As the size of the particle increases, the effect of the impacts average out and the Brownian movement becomes slow. Ultimately, when the dispersed particle becomes big enough to acquire the dimensions of suspension, no Brownian movement is observed.

Option A is correct.