Which of the following statement is incorrect?

Options

A. The atomic radius of Na is greater than that of Mg
B. Metallic bond of Mg is stronger than the metallic bond in Na
C. Melting and boiling point of Mg are greater than those of Ca
D. Mg and Ca are the most abundant elements amongst the alkaline earth metals

Answer

To solve the question of identifying the incorrect statement among the provided options regarding s-block elements, we will analyze each statement step by step.

### Step-by-Step Solution:

1. **Identify the Groups**:
- Group 1: Alkali metals (e.g., Lithium, Sodium, Potassium)
- Group 2: Alkaline earth metals (e.g., Beryllium, Magnesium, Calcium)

2. **Analyze the Statements**:
- **Statement 1**: "The atomic radius of Na is greater than that of Mg."
- **Analysis**: Sodium (Na) is in Group 1 and Magnesium (Mg) is in Group 2. As we move from left to right in the periodic table, the atomic radius decreases due to increased nuclear charge. Therefore, the atomic radius of Na is indeed greater than that of Mg.
- **Conclusion**: This statement is **correct**.

3. **Statement 2**: "The metallic bond of Mg is stronger than that of metallic bond in Na."
- **Analysis**: Magnesium has a smaller atomic radius compared to Sodium, which means the electrons in Magnesium are held more closely to the nucleus, resulting in stronger metallic bonds.
- **Conclusion**: This statement is **correct**.

4. **Statement 3**: "Melting and boiling point of Mg are greater than those of Ca."
- **Analysis**: Calcium (Ca) has a larger metallic lattice than Magnesium (Mg), which means it has stronger metallic bonds. Therefore, it takes more energy to break the bonds in Calcium, leading to a higher melting and boiling point than Magnesium.
- **Conclusion**: This statement is **incorrect**.

5. **Statement 4**: "Magnesium and calcium are the most abundant elements amongst the alkaline earth metals."
- **Analysis**: Magnesium and Calcium are indeed among the most abundant alkaline earth metals in the Earth's crust.
- **Conclusion**: This statement is **correct**.

### Final Conclusion:
The incorrect statement among the options is **Statement 3**: "Melting and boiling point of Mg are greater than those of Ca."