Assertion (A) : `IE_(1)` of `Mg` is greater than that of `Al`.
Reason (R ) : It is easier to remove an electron fro `3s` orbital than
from `3p` orbital.

Options

A. If both A and R are correct and R is the correct explanation for A.
B. If both A and R are correct and R is not the correct explanation for A.
C. If A is correct and R is incorrect
D. If A is incorrect and R is correct

Explanation

To solve the question, we need to analyze the assertion and reason provided.

**Step 1: Understand the Assertion (A)**
The assertion states that the first ionization energy (IE₁) of magnesium (Mg) is greater than that of aluminum (Al).

- Magnesium has the electronic configuration: 1s² 2s² 2p⁶ 3s².
- Aluminum has the electronic configuration: 1s² 2s² 2p⁶ 3s² 3p¹.

**Step 2: Understand the Reason (R)**
The reason states that it is easier to remove an electron from the 3s orbital than from the 3p orbital.

**Step 3: Analyze Ionization Energies**
- The first ionization energy is the energy required to remove the outermost electron from an atom.
- In magnesium, the outermost electrons are in the 3s orbital, while in aluminum, the outermost electron is in the 3p orbital.

**Step 4: Compare the Removal of Electrons**
- The 3s electrons are more tightly held by the nucleus due to the penetration effect. This means they are closer to the nucleus compared to the 3p electrons.
- Therefore, it requires more energy to remove an electron from the 3s orbital than from the 3p orbital.

**Step 5: Conclusion**
- Since it requires more energy to remove an electron from magnesium (3s) than from aluminum (3p), the assertion is correct: IE₁ of Mg is greater than that of Al.
- However, the reason is incorrect because it states the opposite; it is not easier to remove an electron from the 3s orbital than from the 3p orbital.

Thus, the final answer is:
- Assertion (A) is correct.
- Reason (R) is incorrect.

**Final Answer: A is correct and R is incorrect.**

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