According to Hardy Schulze rule, the power of coagulation of an ion depends upon………….

Answer

**Step-by-Step Solution:**

1. **Understanding Hardy-Schulze Rule**: The Hardy-Schulze rule is a principle in colloid chemistry that describes how the coagulation of colloidal particles occurs in the presence of electrolytes. It states that the effectiveness of an electrolyte in causing coagulation depends on the charge and valency of the ions present.

2. **Identifying Key Factors**: According to the rule, the power of coagulation of an ion is influenced primarily by the valency of the coagulating ion. Valency refers to the number of electrons that an atom can lose, gain, or share when it forms chemical bonds.

3. **Comparing Ions**: To illustrate this, we can compare ions such as aluminum (Al³⁺) and magnesium (Mg²⁺). Aluminum has a valency of 3, while magnesium has a valency of 2. According to the Hardy-Schulze rule, aluminum, with its higher valency, will have a greater power of coagulation compared to magnesium.

4. **Conclusion**: Therefore, we can conclude that according to Hardy-Schulze rule, the power of coagulation of an ion depends upon its valency. The higher the valency of the coagulating ion, the greater its ability to cause coagulation.

**Final Answer**: According to Hardy-Schulze rule, the power of coagulation of an ion depends upon its valency.

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