Which of the following pairs is arranged with the particle of higher polarizability listed first?

• A. Cl^- , Br^-
• B. I^- , F^-
• C. O^2- , S^2-
• D. Ne , Ar

Answer: (B)

Verified step by step guidance

1. Understand that polarizability refers to how easily the electron cloud around an ion or atom can be distorted by an external electric field. Larger ions or atoms with more diffuse electron clouds tend to be more polarizable.
2. Recall that polarizability generally increases with increasing size of the ion or atom because larger electron clouds are more easily distorted.
3. Compare the pairs by their positions in the periodic table and their ionic sizes: for example, between Cl⁻ and Br⁻, Br⁻ is larger and thus more polarizable; similarly, between I⁻ and F⁻, I⁻ is larger and more polarizable.
4. For each pair, identify which particle is larger and therefore has higher polarizability. The particle listed first should be the one with the higher polarizability to match the question's requirement.
5. Conclude that the pair where the first particle is larger and more polarizable than the second is the correct answer, which in this case is I⁻ (larger) followed by F⁻ (smaller).