Surface Chemistry(11th And 12th > Chemistry ) Questions and Answers
Which of the following statements are true about peptization? A. A colloidal sol is converted into precipitate B. It is done in the presence of a small electrolyte C. Charges develop on the precipitate during this process D. The charges developed during this process further breaks up into smaller particles of the size of colloids.
Explanation:-
Answer: Option C. -> B,C,D:
C
During peptization, precipitate is converted into a colloidal sol by shaking it with dispersion medium in the presence of a small amount of electrolyte.
Explanation:-
Answer: Option D. -> VcVs=103:
D
Diameter of colloidal particle is about 10 times larger than solute particles in a true solution. Hence, volume is about 1000 times greater i.e. VcVs=103
Explanation:-
Answer: Option C. -> potential difference between fixed charged layer and diffused layer having opposite charge:
C
Zeta potential is the potential difference between fixed charge layer and diffused layer having opposite charge
Explanation:-
Answer: Option D. -> 0.01:
D
10−4g=0.1mg
100 cm3 of gold sol require 0.1 mg
∴10 cm3 of gold sol will required 0.01 mg
Hence, gold number = 0.01.