Most suitable salt which can be used for efficient clotting of blood will be :

Options

A. `NaHCO_3`
B. `FeSO_4`
C. `Mg(HCO_3)_2`
D. `FeCl_3`

Answer

To determine the most suitable salt for efficient blood clotting, we need to analyze the options provided and understand the role of certain ions in the coagulation process.

### Step-by-Step Solution:

1. **Understanding Blood Clotting**: Blood clotting is a complex process that involves the aggregation of blood cells and proteins to form a solid mass (clot). Certain ions and compounds can facilitate this process.

2. **Analyzing the Options**:
- **FeCl3 (Ferric Chloride)**: This compound contains Fe³⁺ ions. Ferric ions can interact with negatively charged components in the blood, promoting coagulation.
- **FeS (Iron(II) Sulfide)**: This compound does not provide the necessary ions for effective clotting and is not typically associated with coagulation.
- **Magnesium Hydroxide**: This compound does not play a significant role in blood clotting.
- **None of these**: This option suggests that none of the provided salts are suitable for blood clotting.

3. **Role of Ferric Ions**: Ferric ions (Fe³⁺) are known to stabilize the colloidal nature of blood and promote coagulation. According to the Hardy-Schulze rule, the coagulation of colloids is enhanced by the presence of ions with higher charges.

4. **Conclusion**: Among the options given, FeCl3 is the most suitable salt for efficient blood clotting due to its ability to provide ferric ions that facilitate coagulation.

### Final Answer:
The most suitable salt which can be used for efficient clotting of blood is **FeCl3 (Ferric Chloride)**.

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