Hardy-Schulze law states that

Options

A. larger the charge on the coagulating ions, greater is its coagulating power, having opposite sign of solution
B. solution must have zero gold number
C. disperse phase and dispersion medium must be of the same sign
D. micelles coagulate in presence of surfactants

Answer

**Step-by-Step Solution:**

1. **Understanding Hardy-Schulze Law**: The Hardy-Schulze law is a principle in colloidal chemistry that describes the relationship between the valency of ions and their ability to coagulate colloidal solutions.

2. **Definition of Coagulation**: Coagulation is the process where colloidal particles aggregate to form larger particles. This process is crucial in various applications, including water treatment and food processing.

3. **Role of Electrolytes**: According to the Hardy-Schulze law, the amount of electrolyte needed to coagulate a specific amount of colloidal solution is influenced by the valency of the coagulating ion.

4. **Coagulating Ion**: The coagulating ion is the ion that has a charge opposite to that of the colloidal particles. For example, if the colloidal particles are negatively charged, the coagulating ion will be positively charged.

5. **Valency and Coagulating Power**: The law states that the coagulating power of an ion increases with its valency. This means that ions with higher charges (greater valency) are more effective at causing coagulation.

6. **Conclusion**: In summary, the Hardy-Schulze law indicates that the effectiveness of an electrolyte in coagulating a colloidal solution is directly related to the valency of the coagulating ion. Higher valency ions will require a smaller amount to achieve the same coagulation effect compared to ions with lower valency.

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