Of the following metal ions, which has the largest magnetic moment in ...
Low spin cr 2+ have 2 unpaired electrons. Fe3+ and co2+ have only one unpaired electrons and co3+ have no unpaired electrons. if no. of unpaired electrons increases., It's magnetic moment also increases., because it only depends upon no. Of unpaired electrons.
Of the following metal ions, which has the largest magnetic moment in ...
Explanation:
Magnetic moment is a measure of the strength of a magnetic field created by an atom or ion. It is influenced by the number of unpaired electrons present in the system. In low-spin octahedral complexes, the ligands cause the d-orbitals to split into two sets of three, known as the t2g and eg orbitals. The electrons fill the t2g orbitals first before occupying the eg orbitals.
Let's consider each option given in the question and evaluate their magnetic moments in low-spin octahedral complexes.
a) Fe3+: In its low-spin octahedral complexes, Fe3+ has five d-electrons. The electrons fill the t2g orbitals first, leaving only one electron in the eg orbital. Therefore, Fe3+ has a low magnetic moment of 5.9 BM (Bohr magneton).
b) Co3+: In its low-spin octahedral complexes, Co3+ has six d-electrons. The electrons fill the t2g orbitals first, leaving no electrons in the eg orbital. Therefore, Co3+ has a moderate magnetic moment of 3.9 BM.
c) Co2+: In its low-spin octahedral complexes, Co2+ has four d-electrons. The electrons fill the t2g orbitals first, leaving two electrons in the eg orbital. Therefore, Co2+ has a high magnetic moment of 4.8 BM.
d) Cr2+: In its low-spin octahedral complexes, Cr2+ has four d-electrons. The electrons fill the t2g orbitals first, leaving two electrons in the eg orbital. However, unlike Co2+, the two electrons in the eg orbital are paired, resulting in a cancellation of their magnetic moments. Therefore, Cr2+ has a low magnetic moment of 0 BM.
Therefore, the correct answer is option D, Cr2+.