coagultion is the process by which the dispersed phase of a colloid is made to aggregate and thereby separtate from the continuous phase. The minimum concetration of an eletrolyte in milli-moles per litre of the electrolyte solution which required to cause the caogultion of colloidal sol is called coagution value .
therefroe higher is the coagulatings power of effective ion, smaller will be the coagultion value of the electrolyte.
coagultion value ` propto = 1/("coagulating power")`
the coagulation values of differnt electrolytes are different . this behavious can be easily uderstood by Harby - schulze rule which states.
the greater is the valency of the effective ion grreater is its coagulating power,"
which one had the highest coagulating powe?

Options

A. `K^(+)`
B. `Ca^(2+)`
C. `Al^(3+)`
D. `Sn^(4+)`

Answer

To determine which ion has the highest coagulating power based on the information provided, we can follow these steps:

### Step 1: Understand Coagulation
Coagulation is the process where the dispersed phase of a colloid aggregates and separates from the continuous phase.

### Step 2: Define Coagulation Value
The coagulation value is the minimum concentration of an electrolyte required to cause coagulation, measured in millimoles per liter.

### Step 3: Relationship Between Coagulating Power and Coagulation Value
The coagulating power of an ion is inversely proportional to its coagulation value. This means that a higher coagulating power corresponds to a lower coagulation value.

### Step 4: Apply Hardy-Schulze Rule
According to the Hardy-Schulze rule, the coagulating power of an ion increases with its valency. Therefore, ions with higher valency will have greater coagulating power.

### Step 5: Identify the Ions and Their Valencies
To find out which ion has the highest coagulating power, we need to compare the valencies of the ions given in the options. For example:
- \( \text{Na}^+ \) has a valency of 1.
- \( \text{Ca}^{2+} \) has a valency of 2.
- \( \text{Al}^{3+} \) has a valency of 3.
- \( \text{Sn}^{4+} \) has a valency of 4.

### Step 6: Determine the Highest Valency
Among the ions listed, \( \text{Sn}^{4+} \) has the highest valency of 4.

### Step 7: Conclusion
Since \( \text{Sn}^{4+} \) has the highest valency, it will have the highest coagulating power according to the Hardy-Schulze rule.

### Final Answer
The ion with the highest coagulating power is \( \text{Sn}^{4+} \).

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