Ferric chloride is applied to stop bleeding because:

Options

A. `Fe^(3+)` ion coagulates blood, which is a negatively charged sol
B. `Fe^(3+)` ion coagulates blood, which is a positively charged sol
C. `Cl_(–)` coagulates blood, which is a positively charged sol
D. `Cl^(–)` ion coagulates blood, which is a negatively charged sol

Answer

To answer the question of why ferric chloride is applied to stop bleeding, we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Understanding Coagulation**:
- Coagulation is a process where small particles suspended in a liquid clump together to form larger aggregates. This is crucial in stopping bleeding as it helps in forming a clot.

**Hint**: Coagulation is the process that helps in clumping particles together.

2. **Nature of Blood**:
- Blood can be described as a colloidal solution, where the dispersed phase is solid (cells) and the dispersion medium is liquid (plasma).

**Hint**: Remember that blood is a colloid, which means it has solid particles dispersed in a liquid.

3. **Role of Ferric Chloride**:
- Ferric chloride (FeCl₃) dissociates in solution to release Fe³⁺ ions. These ions are positively charged.

**Hint**: Ferric chloride releases positively charged ions when dissolved.

4. **Charge Interaction**:
- The negatively charged components of blood (such as proteins) interact with the positively charged Fe³⁺ ions. According to the Hardy-Schulze rule, the higher the charge of the cation, the greater its coagulation power.

**Hint**: Higher charge on cations leads to better coagulation of negatively charged particles.

5. **Application of Hardy-Schulze Rule**:
- The Fe³⁺ ions from ferric chloride effectively coagulate the negatively charged particles in blood, promoting clot formation and thus stopping the bleeding.

**Hint**: Use the Hardy-Schulze rule to understand how charges interact for coagulation.

6. **Conclusion**:
- Therefore, ferric chloride is applied to stop bleeding because the Fe³⁺ ions coagulate the negatively charged components of blood, facilitating the formation of a clot.

**Hint**: The main reason ferric chloride is used is due to the coagulation effect of Fe³⁺ ions on negatively charged blood components.

### Final Answer:
Ferric chloride is applied to stop bleeding because Fe³⁺ ions coagulate blood, which is negatively charged, leading to the formation of a clot.