Given below are two statements : Statement (I): The metallic radius of Al is less than that of Ga. Statement (II): The ionic radius of mathrmAl^3+$\mathrm{Al}^{3+}$ is less than that of mathrmGa^3+$\mathrm{Ga}^{3+}$. In the light of the above statements, choose the most appropriate answer from the options given below:

### Related Formula Effective nuclear charge scaling expression layout: Z_texteff = Z - sigma$$Z_{\text{eff}} = Z - \sigma$$ ### Core Logic Let's analyze both properties systematically: * **Statement I**: The metallic radius of Gallium (mathrmGa$\mathrm{Ga}$) is anomalously *smaller* than Aluminum (mathrmAl$\mathrm{Al}$) due to the poor shielding effect of the 10$10$ d-electrons inserted before it. This increases Z_texteff$Z_{\text{eff}}$, pulling the outer shell inward tightly. Thus, textRadius of Al > textRadius of Ga$\text{Radius of Al} > \text{Radius of Ga}$, making Statement I incorrect. * **Statement II**: When looking at completely stripped ionic configurations (mathrmAl^3+$\mathrm{Al^{3+}}$ and mathrmGa^3+$\mathrm{Ga^{3+}}$), the extra shell layer in Gallium resumes its dominant role, meaning standard periodic increase down a group holds true: mathrmAl^3+ < Ga^3+$\mathrm{Al^{3+} < Ga^{3+}}$. (Statement II is correct). ### Step 1: Evaluation Thus, Statement I is incorrect but Statement II is correct. ### Pattern Recognition This is a classic trap: d-block contraction reverses the atomic/metallic radius trend line between Al and Ga, but does NOT reverse the ionic radius sequence line where Ga3+ is larger than Al3+. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Chemistry: Classification of Elements and Periodicity in Properties Class 11 Chemistry: The p-Block Elements