Chemistry · CHEMICAL BONDING AND MOLECULAR STRUCTURE

According to Fajans' rules, which of the following pairs of cations exhibits the greater polarising power for the first member of the pair over the second, primarily due to pseudo-noble gas configuration rather than ionic charge or size?

1. A
   \( \text{Cu}^+ \) compared to \( \text{Na}^+ \)
2. B
   \( \text{Mg}^{2+} \) compared to \( \text{Ba}^{2+} \)
3. C
   \( \text{Al}^{3+} \) compared to \( \text{Mg}^{2+} \)
4. D
   \( \text{Ca}^{2+} \) compared to \( \text{K}^+ \)