Among the following options, select the option in which each complex in
Set-I shows geometrical isomerism and the two complexes in
Set-II are ionization isomers of each other.
[en = H2NCH2CH2NH2]
Set-I Analysis:
Set-II Analysis:
\([Co(NH_3)_5Cl]SO_4\) and \([Co(NH_3)_5(SO_4)]Cl\): These two complexes are ionization isomers because they differ in the ion released in solution.
Conclusion:
Option (C) satisfies both conditions:
To solve the problem, we analyze both sets to find complexes showing geometrical isomerism in Set-I and ionization isomers in Set-II.
1. Geometrical Isomerism in Set-I:
- [Co(NH3)3(NO2)3] does not show geometrical isomerism as it contains identical ligands.
- [Co(en)2Cl2] contains two bidentate ethylenediamine (en) ligands and two chloride ligands; it exhibits cis and trans geometrical isomers.
Hence, these two complexes are suitable for geometrical isomerism.
2. Ionization Isomers in Set-II:
- [Co(NH3)5Cl]SO4 and [Co(NH3)5(SO4)]Cl differ by interchange of ligands inside and outside coordination sphere, so they are ionization isomers.
Final Answer:
Set-I: [Co(NH3)3(NO2)3] and [Co(en)2Cl2]
Set-II: [Co(NH3)5Cl]SO4 and [Co(NH3)5(SO4)]Cl
This matches option C.
The steam volatile compounds among the following are:

The structure of the major product formed in the following reaction is:

The center of a disk of radius $ r $ and mass $ m $ is attached to a spring of spring constant $ k $, inside a ring of radius $ R>r $ as shown in the figure. The other end of the spring is attached on the periphery of the ring. Both the ring and the disk are in the same vertical plane. The disk can only roll along the inside periphery of the ring, without slipping. The spring can only be stretched or compressed along the periphery of the ring, following Hooke’s law. In equilibrium, the disk is at the bottom of the ring. Assuming small displacement of the disc, the time period of oscillation of center of mass of the disk is written as $ T = \frac{2\pi}{\omega} $. The correct expression for $ \omega $ is ( $ g $ is the acceleration due to gravity): 
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