The coagulating power of an electrolyte for blood decrease in the order.

Options

A. `Na^(+), Al^(+3), Ba^(+2)`
B. `PO_(4)^(-3), SO_(4)^(-2), Cl^(-)`
C. `Al^(+3), Ba^(+2), Na^(+)`
D. `Cl^(-),SO_(4)^(2-), PO_(4)^(-3)`

Answer

To determine the coagulating power of an electrolyte for blood, we need to consider the valency of the ions involved. The coagulating power of an electrolyte is influenced by the charge of the ions; higher charged ions have a greater coagulating power.

### Step-by-Step Solution:

1. **Understand Coagulating Power**: The coagulating power of an electrolyte is determined by its ability to neutralize the negative charges on colloidal particles in blood. The more positive charge an ion has, the more effective it is at coagulating.

2. **Identify the Ions and Their Charges**:
- Na⁺ (Sodium) has a charge of +1.
- Ba²⁺ (Barium) has a charge of +2.
- Al³⁺ (Aluminum) has a charge of +3.

3. **Rank the Ions by Charge**:
- The ion with the highest positive charge will have the greatest coagulating power. Therefore, we rank them as follows:
- Al³⁺ (highest charge)
- Ba²⁺ (middle charge)
- Na⁺ (lowest charge)

4. **Determine the Decreasing Order**: Based on the charges, the order of coagulating power from highest to lowest is:
- Al³⁺ > Ba²⁺ > Na⁺

5. **Select the Correct Option**:
- From the options provided, the correct order of coagulating power is found in option C: Al³⁺, Ba²⁺, Na⁺.

### Final Answer:
The coagulating power of an electrolyte for blood decreases in the order: **Al³⁺ > Ba²⁺ > Na⁺** (Option C).

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