The strong oxidising agent is Co\(^3{+}\).
The number of unpaired electrons in Co\(^3{+}\) (\([3d^6]\)) is 4.
The spin-only magnetic moment is given by: \[ \mu = \sqrt{n(n+2)} \, \text{BM} \]
Substituting \(n = 4\):
\[ \mu = \sqrt{4(4+2)} = \sqrt{24} \approx 5 \, \text{BM} \]
Give explanation for each of the following observations:
(a) With the same d-orbital configuration (d4), Mn3+ ion is an oxidizing agent whereas Cr2+ ion is a reducing agent.
(b) Actinoid contraction is greater from element to element than that among lanthanoids.
(c) Transition metals form a large number of interstitial compounds with H, B, C, and N.
A transition metal (M) among Mn, Cr, Co and Fe has the highest standard electrode potential \( (M^{3+} / M^{2+}) \). It forms a metal complex of the type \( [M(CN)_6]^{4-} \). The number of electrons present in the \( e_g \) orbital of the complex is ________.
Let the lines $L_1 : \vec r = \hat i + 2\hat j + 3\hat k + \lambda(2\hat i + 3\hat j + 4\hat k)$, $\lambda \in \mathbb{R}$ and $L_2 : \vec r = (4\hat i + \hat j) + \mu(5\hat i + + 2\hat j + \hat k)$, $\mu \in \mathbb{R}$ intersect at the point $R$. Let $P$ and $Q$ be the points lying on lines $L_1$ and $L_2$, respectively, such that $|PR|=\sqrt{29}$ and $|PQ|=\sqrt{\frac{47}{3}}$. If the point $P$ lies in the first octant, then $27(QR)^2$ is equal to}