Consider the following three complexes: \(\left(\right.\) Complex 1) $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Br}_{2}\right] \mathrm{Cl}$ 2) \(\left[\mathrm{Pd}\left(\mathrm{NH}_{3}\right)_{2}(\mathrm{ONO})_{2}\right]\) (Complex (Complex 3) $\left[\mathrm{V}(\mathrm{en})_{2} \mathrm{Cl}_{2}\right]^{+},$ Which of the three complexes can have (a) geometric isomers, (b) linkage isomers, (c) optical isomers, (d) coordinationsphere isomers?

Complex 1 is a six-coordinate complex with tetraammine and two bromine ligands. To check for the presence of different types of isomers, we can consider the following: (a) Geometric isomers: Since it's an octahedral complex, it can exhibit geometrical isomerism in the form of cis and trans configurations. In this case, there are cis and trans isomers possible due to the different arrangement of bromine ligands around the cobalt center. (b) Linkage isomers: As there are no ligands with ambidentate bonding in this complex, it cannot form any linkage isomers. (c) Optical isomers: Due to the presence of two bromine ligands, the cis-form of this complex will exhibit optical isomerism (it has a non-superimposable mirror image). (d) Coordination-sphere isomers: This complex cannot have coordination-sphere isomers as all the ligands are within the same coordination sphere.

In Complex 2, there are four ligands around the center metal: two ammonia and two nitro ligands. (a) Geometric isomers: Given the square-planar geometry of this complex, it can have cis and trans configurations due to the difference in the arrangement of ammonia and nitro ligands around the palladium center. (b) Linkage isomers: The nitro ligands can form linkage isomers when bonded through nitrogen instead of oxygen, forming the nitrito ligand. (c) Optical isomers: Since it is a square-planar complex, it cannot have optical isomers. (d) Coordination-sphere isomers: This complex cannot have coordination-sphere isomers as all the ligands are within the same coordination sphere.

Complex 3 is an octahedral complex with two ethylenediamine (en) ligands and two chloride ligands. (a) Geometric isomers: This complex shows geometric isomerism, with cis and trans isomers differing in the arrangement of chloride ligands around the vanadium center. (b) Linkage isomers: As there are no ligands with ambidentate bonding in this complex, it cannot form any linkage isomers. (c) Optical isomers: The cis-form of this complex is optically active and will have non-superimposable mirror images, making it an optically active complex. (d) Coordination-sphere isomers: This complex cannot have coordination-sphere isomers as all the ligands are within the same coordination sphere. In summary, the three complexes exhibit the following isomers: Complex 1: (a) Geometric isomers, (c) Optical isomers Complex 2: (a) Geometric isomers, (b) Linkage isomers Complex 3: (a) Geometric isomers, (c) Optical isomers