
Which of the following cations will have minimum flocculation value for an arsenic sulphide solution:
A. $N{{a}^{+}}$
B. $M{{g}^{2+}}$
C. $C{{a}^{2+}}$
D. $A{{l}^{3+}}$
Answer
150k+ views
Hint: Think about the Hardy-Schulz law, and how it relates the flocculation value with coagulation power and the charge present on the cations.
Complete step by step solution:
* Flocculation is basically aggregating small, colloidal particles (negatively charged in this example) and gathering large sized particles which can later separate and settle down as a precipitate. The flocculating ion (positively charged in this example) does this job of aggregating the small, colloidal particles that need to be precipitated.
* The flocculation value is the minimum concentration of these flocculating ions that is required to flocculate all the colloidal particles in the solution.
* The greater the charge on the flocculating ion, the more negatively charged colloidal particles it can neutralize and coagulate. Thus, the greater the charge on the flocculating ion, the greater the coagulation power of that ion.
* If the number of colloidal particles the flocculating ion can neutralize increases, this implies that less amount of the flocculating ion will be required to flocculate all the colloidal particles in the solution. Hence, the greater the charge on the ion, the less the flocculation value.
Thus, as the Hardy-Schulz law states and we deduced:
\[\text{Charge }\alpha \text{ }\dfrac{1}{\text{flocculation value}}\]
Hence, among the options given, aluminium has the most amount of charge. The answer is ‘D. $A{{l}^{3+}}$’
Note: Please do not get confused between flocculation and coagulation, they refer to the same phenomenon but different aspects of it. Coagulation is the neutralization of charged colloidal particles, and flocculation is the aggregation of all the coagulated material and its precipitation.
Complete step by step solution:
* Flocculation is basically aggregating small, colloidal particles (negatively charged in this example) and gathering large sized particles which can later separate and settle down as a precipitate. The flocculating ion (positively charged in this example) does this job of aggregating the small, colloidal particles that need to be precipitated.
* The flocculation value is the minimum concentration of these flocculating ions that is required to flocculate all the colloidal particles in the solution.
* The greater the charge on the flocculating ion, the more negatively charged colloidal particles it can neutralize and coagulate. Thus, the greater the charge on the flocculating ion, the greater the coagulation power of that ion.
* If the number of colloidal particles the flocculating ion can neutralize increases, this implies that less amount of the flocculating ion will be required to flocculate all the colloidal particles in the solution. Hence, the greater the charge on the ion, the less the flocculation value.
Thus, as the Hardy-Schulz law states and we deduced:
\[\text{Charge }\alpha \text{ }\dfrac{1}{\text{flocculation value}}\]
Hence, among the options given, aluminium has the most amount of charge. The answer is ‘D. $A{{l}^{3+}}$’
Note: Please do not get confused between flocculation and coagulation, they refer to the same phenomenon but different aspects of it. Coagulation is the neutralization of charged colloidal particles, and flocculation is the aggregation of all the coagulated material and its precipitation.
Recently Updated Pages
JEE Main 2021 July 25 Shift 1 Question Paper with Answer Key

JEE Main 2021 July 22 Shift 2 Question Paper with Answer Key

JEE Atomic Structure and Chemical Bonding important Concepts and Tips

JEE Amino Acids and Peptides Important Concepts and Tips for Exam Preparation

JEE Electricity and Magnetism Important Concepts and Tips for Exam Preparation

Chemical Properties of Hydrogen - Important Concepts for JEE Exam Preparation

Trending doubts
JEE Main 2025 Session 2: Application Form (Out), Exam Dates (Released), Eligibility, & More

JEE Main 2025: Derivation of Equation of Trajectory in Physics

Learn About Angle Of Deviation In Prism: JEE Main Physics 2025

Electric Field Due to Uniformly Charged Ring for JEE Main 2025 - Formula and Derivation

Degree of Dissociation and Its Formula With Solved Example for JEE

Electrical Field of Charged Spherical Shell - JEE

Other Pages
JEE Advanced Marks vs Ranks 2025: Understanding Category-wise Qualifying Marks and Previous Year Cut-offs

JEE Advanced 2025: Dates, Registration, Syllabus, Eligibility Criteria and More

JEE Advanced Weightage 2025 Chapter-Wise for Physics, Maths and Chemistry

Ideal and Non-Ideal Solutions Raoult's Law - JEE

NCERT Solutions for Class 11 Chemistry In Hindi Chapter 1 Some Basic Concepts of Chemistry

JEE Advanced 2025 Notes
