Question

The spin-only magnetic moment value of $M ^{3+}$ ion (in gaseous state) from the pairs $Cr ^{3+} / Cr ^{2+}, Mn ^{3+} / Mn ^2, \quad Fe ^{3+} / Fe ^{2+}$ and $Co ^{3+} / Co ^{2+}$ that has negative standard electrode potential, is BM [Nearest integer]

Answer 1

The correct answer is 4
ECr+30​∣∣​Cr+2​=−0.41V
[Cr+3]=4s03d3
μ=n(n+2)​ B.M
=15​ B.M ∼4 B.M