The crystal field stabilization energy (CFSE) depends on the oxidation state and the ligand field strength.
Generally:
- The higher the oxidation state of the metal, the stronger the ligand field and the higher the CFSE.
- \( \text{NH}_3 \) is a stronger field ligand than \( \text{en} \) (ethylenediamine).
Thus: - \( [\text{Co(NH}_3)_4]^{2+} \) will have the lowest CFSE, as it is in a lower oxidation state.
- \( [\text{Co(NH}_3)_6]^{2+} \) has a higher CFSE compared to \( [\text{Co(NH}_3)_4]^{2+} \).
- \( [\text{Co(NH}_3)_6]^{3+} \) has a higher oxidation state, leading to higher CFSE.
- \( [\text{Co(en)}_3]^{3+} \) has the highest CFSE due to the strong ligand field of \( \text{en} \).
Hence, the correct order is:
\[[\text{Co(NH}_3)_4]^{2+} < [\text{Co(NH}_3)_6]^{2+}<[\text{Co(NH}_3)_6]^{3+} < [\text{Co(en)}_3]^{3+}\]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,