Question

Which of the following compounds can exhibit fac-mer isomerism?

A. [Cu(CO)5Cl]+
B. [Fe(CO)5NO2]2+
C. [Cr(H2O)4Br2]+
D. [Fe(NH3)2(H2O)4]2+
E. [Co(H2O)3(CO)3]3+

Answer 1

[Co(H2O)3(CO)3]3+

Step-by-step explanation:

If an octahedral specie has the general formula EX3Y3, the X groups may be arranged to be on one face of the octahedron and the Y groups may also be arranged to be on the other face of the octahedron or lie in the plane of the central atom.

The two stereo isomers described above are called fac (facial) and mer (meridional) isomers.

Only [Co(H2O)3(CO)3]3+ can exhibit this type of isomerism among the options in the questions since it has the general formula, EX3Y3.