Question #44585

In the 3d transition series, metal $M_1$ exhibits an anomalously negative standard reduction potential ($E^\circ_{M^{2+}/M}$) primarily due to its exceptionally high negative hydration enthalpy. Metal $M_2$ also shows a sharp negative discontinuity in its $E^\circ_{M^{2+}/M}$ trend, but this is driven by the low sum of its first two ionization enthalpies associated with a stable half-filled $d$-subshell.

Aqueous solutions of $M_1^{2+}$ and $M_2^{2+}$ are treated with excess \ce{KCN(aq)} under an inert atmosphere at 298 K to form the major complex ions $P$ and $Q$, respectively.

Which of the following correctly identifies the spin-only magnetic moment ($\mu$) of $P$, the spin-only magnetic moment of $Q$, and the Crystal Field Stabilization Energy (CFSE) of $Q$? (Assume $\Delta_o > P$ for octahedral complexes. Express CFSE in terms of the octahedral splitting energy $\Delta_o$ and the mean pairing energy $P$).