In which state iron is present in haemoglobin.

Options

A. Anionic
B. `Fe^(2+)`
C. `Fe^(3+)`
D. None of these

Answer

### Step-by-Step Solution:

1. **Understanding Hemoglobin**: Hemoglobin is a globular protein found in red blood cells, responsible for transporting oxygen (O2) throughout the body.

2. **Structure of Hemoglobin**: Each hemoglobin molecule consists of four peptide subunits. These subunits are held together by various types of bonds, including ionic bonds, hydrogen bonds, hydrophobic interactions, and van der Waals forces.

3. **Hem Group Composition**: Each of the four subunits contains a heme group. The heme group is crucial for the function of hemoglobin as it binds oxygen.

4. **Iron in Hemoglobin**: The heme group contains iron, which is essential for oxygen binding. The iron in the heme group is in the ferrous state, denoted as Fe²⁺ (Fe2 plus).

5. **Identifying the Correct State of Iron**: The question asks for the state of iron present in hemoglobin. The options provided include:
- Anionic
- Fe²⁺ (Ferrous)
- Fe³⁺ (Ferric)
- None of these

6. **Conclusion**: The correct answer is that iron is present in the ferrous state (Fe²⁺) in hemoglobin. Therefore, the right option is Fe²⁺.

### Final Answer:
The state of iron present in hemoglobin is **Fe²⁺ (ferrous state)**.

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