Discuss Question - AllPreviousYears

Correct Answer: B. Cations decrease in size and anions increase in size across a period.
Explanation: The ionic radius across a period generally decreases for both cations and anions due to the increase in effective nuclear charge. For cations, losing electrons increases the net attraction from the nucleus, causing the remaining electron shells to pull inward. As you move from left to right, the ionic size of these cations progressively shrinks. When reaching the non-metal section where anions form, there is a sharp increase in radius because the added electrons experience more repulsion; however, within the anion series itself, the radius continues to decrease as the atomic number increases. Consequently, across a typical period, the size of cations decreases and the size of anions also decreases, making the correct trend one where both types of ions become smaller as the nuclear charge increases.

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