Haemoglobin is a complex of_______ chlorophyll is a complex of_______ and vitamin `B_(12)` is a complex of_________ .

Answer

To answer the question, we need to fill in the blanks regarding the complexes of hemoglobin, chlorophyll, and vitamin B12. Here’s the step-by-step solution:

### Step 1: Hemoglobin
- **Identify what hemoglobin is**: Hemoglobin is a red pigment found in blood that is responsible for transporting oxygen from the lungs to the rest of the body.
- **Determine the metal ion in hemoglobin**: The central metal ion in hemoglobin is iron (Fe).
- **Fill in the blank**: Hemoglobin is a complex of **iron**.

### Step 2: Chlorophyll
- **Identify what chlorophyll is**: Chlorophyll is a green pigment found in plants that plays a crucial role in photosynthesis.
- **Determine the metal ion in chlorophyll**: The central metal ion in chlorophyll is magnesium (Mg).
- **Fill in the blank**: Chlorophyll is a complex of **magnesium**.

### Step 3: Vitamin B12
- **Identify what vitamin B12 is**: Vitamin B12, also known as cobalamin, is essential for red blood cell formation and neurological function.
- **Determine the metal ion in vitamin B12**: The central metal ion in vitamin B12 is cobalt (Co).
- **Fill in the blank**: Vitamin B12 is a complex of **cobalt**.

### Final Answer
- Hemoglobin is a complex of **iron**.
- Chlorophyll is a complex of **magnesium**.
- Vitamin B12 is a complex of **cobalt**.

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