Question

# Coordination number of cobalt in ${\left[ {Co{{\left( {{C_2}{O_4}} \right)}_3}} \right]^{3 - }}$ is-(A) 2(B) 6(C) 5(D) 4

In the given complex the number of coordinated ligand sites is equal. Since in ${\left[ {Co{{\left( {{C_2}{O_4}} \right)}_3}} \right]^{3 - }}$ the ${C_2}O_4^{2 - }$ ligand is present which is a bidentate ligand and the coordinating number is therefore 6.