For which of the following isoelectronic species is the effective nuclear charge () strictly the hig — Periodic Table and Periodicity Chemistry Question

💡 Solution & Explanation

All species have 18 electrons. Effective nuclear charge ($Z_{eff}$) is directly proportional to the number of actual protons ($Z$). $Ca^{2+}$ has the highest $Z$ (20 protons), hence the highest $Z_{eff}$.