Choose the correct statement regarding transition elements?

Options

A. Transition elements has low melting points
B. transition elements do not have catalytic activity
C. Transition elements exhibit variable states
D. Transition elements exhibit inert pair effect

Answer

To solve the question regarding the correct statement about transition elements, we will analyze each of the provided statements one by one.

### Step-by-Step Solution:

1. **Understand Transition Elements**:
Transition elements are defined as elements that have partially filled d-orbitals. They are found in the d-block of the periodic table.

2. **Evaluate the Statements**:
- **Statement 1**: "Transition elements have low melting point."
- **Analysis**: This statement is incorrect. Transition elements generally have high melting points due to strong metallic bonding and the presence of d-electrons.

- **Statement 2**: "Transition elements do not have catalytic efficiency."
- **Analysis**: This statement is also incorrect. Transition elements are known for their catalytic properties. For example, iron is used as a catalyst in the Haber process for ammonia synthesis, and nickel is used in hydrogenation reactions.

- **Statement 3**: "Transition elements exhibit variable oxidation states."
- **Analysis**: This statement is correct. Transition elements can exhibit multiple oxidation states due to the involvement of d-electrons in bonding. For example, manganese can show oxidation states ranging from +2 to +7.

- **Statement 4**: "Transition elements exhibit inert-pair effect."
- **Analysis**: This statement is incorrect. The inert-pair effect is observed in post-transition metals, not in transition metals. Transition metals do not typically show this effect.

3. **Conclusion**:
After evaluating all the statements, the only correct statement regarding transition elements is:
- **Statement 3**: "Transition elements exhibit variable oxidation states."

### Final Answer:
The correct statement regarding transition elements is: **"Transition elements exhibit variable oxidation states."**

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