question_answer 10)

The hexaaquamanganese(II) ion contains five unpaired electrons while the hexacyano ion contains only one unpaired electron. Explain using Crystral field theory.

Answer:

Ans.       Mn in +2 state has the configuration 3d5. In present of H2O which is weak ligand, the distribution of these five electrons is i.e., all the electrons remain unpaired. In presence of CN? which is a strong ligand, the distribution is  i.e., two t2g orbitals contain paired electrons while the third orbital contains one unpaired electron.