To determine the order of complex ions according to their spin-only magnetic moment values, we need to consider the electronic configuration and the number of unpaired electrons in each complex ion.
The spin-only magnetic moment (\( \mu_s \)) is calculated using the formula:
\(\mu_s = \sqrt{n(n+2)}\) B.M.
where \( n \) is the number of unpaired electrons.
Iron is in the \( +3 \) oxidation state. Electronic configuration of Fe\(^{3+}\) is 3d5. Fluoride ion (F\(^-\)) is a weak field ligand, so it will not cause pairing of electrons. Hence, all the 5 d-electrons remain unpaired.
Number of unpaired electrons in \( P \) = 5.
Magnetic moment, \(\mu_s = \sqrt{5(5+2)} = \sqrt{35} \approx 5.92\) B.M.
Vanadium is in the \( +2 \) oxidation state. Electronic configuration of V\(^{2+}\) is 3d3. Water (H\(_2\)O) is a weak field ligand and does not cause pairing of electrons. Therefore, all 3 d-electrons remain unpaired.
Number of unpaired electrons in \( Q \) = 3.
Magnetic moment, \(\mu_s = \sqrt{3(3+2)} = \sqrt{15} \approx 3.87\) B.M.
Iron is in the \( +2 \) oxidation state. The electronic configuration of Fe\(^{2+}\) is 3d6. Water is a weak field ligand and does not cause pairing. Thus, 4 d-electrons remain unpaired.
Number of unpaired electrons in \( R \) = 4.
Magnetic moment, \(\mu_s = \sqrt{4(4+2)} = \sqrt{24} \approx 4.90\) B.M.
Based on the magnetic moment values calculated, the correct order is:
Q < R < P
μ = √5(5 + 2) = √35 BM
μ = √3(3 + 2) = √15 BM
μ = √4(4 + 2) = √24 BM
Thus, the correct order of magnetic moments is Q < R < P.
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)

Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)
A black body is at a temperature of 2880 K. The energy of radiation emitted by this body with wavelength between 499 nm and 500 nm is U1, between 999 nm and 1000 nm is U2 and between 1499 nm and 1500 nm is U3. The Wien's constant, b = 2.88×106 nm-K. Then,