question_answer

The complex ion that will lose its crystal field stabilization energy upon oxidation of its metal to +3 state is                                                                           [JEE Main Held on 12-4-2019 Morning]

A) \[{{[Fe{{(phen)}_{3}}]}^{2+}}\]

B) \[{{[Zn{{(phen)}_{3}}]}^{2+}}\]

C) \[{{[Ni{{(phen)}_{3}}]}^{2+}}\]             

D) \[{{[Co{{(phen)}_{3}}]}^{2+}}\]

Correct Answer: A

Solution :

            symmetrical bidentate ligand. By oxidation of \[F{{e}^{2+}}\]into \[F{{e}^{3+}},\]the CFSE value decrease. By oxidation of \[Z{{n}^{2+}}\]into \[Z{{n}^{3+}},\]the CFSE value increase. by oxidation of \[N{{i}^{2+}}\]into \[N{{i}^{3+}},\]the CFSE value increase. by oxidation of \[C{{o}^{2+}}\]into \[C{{o}^{3+}},\]the CFSE value increase.