A metal ion in a high-spin octahedral complex has two more unpaired electrons than the same ion does in a low-spin octahedral complex. Which of the following could the metal ion be?

Question

Quizplus · Accepted Answer

In a high-spin octahedral complex, there are 4 unpaired electrons, while in a low-spin octahedral complex, there are 2 unpaired electrons. Therefore, the metal ion must have an electronic configuration of d4 in a low-spin complex and d6 in a high-spin complex. Among the given options, only Co2+ satisfies this condition, as it has d7 electronic configuration with 3 unpaired electrons in a low-spin complex and 5 unpaired electrons in a high-spin complex. Thus, the correct answer is option C, Co²⁺.

A Metal Ion in a High-Spin Octahedral Complex Has Two