Question

Q1. The following species a)-c) all contain complex ions of transition metals, which you can assume take up an octahedral geometry.

a) [RuCl3(H2O)3]

b) [Ir(bpy)3]Cl3 ; bipy = 2,2'-bipyridine

c) K2[Mo(NCS)6] For each species:

i) draw all the possible isomers of the complex ions;

ii) calculate the charge of the metal, and the dn configuration;

iii) draw a diagram showing d orbital occupancy and, where high and low spin cases are possible, predict which will be favoured considering the spectrochemical series

Q2. Explain the following reactions by reference to crystal field splitting and the spectrochemical series.

4[Co(H2O)6] 3+(aq) + 2H2O 4[Co(H2O)6] 2+(aq) + O2 + 4H+

4[Co(NH3)6] 2+(aq) + O2 + 4H+ 4[Co(NH3)6] 3+(aq) + 2H2O

(both processes are spontaneous)

Answer 1

2,2′-Bipyridine (bipy or bpy, pronounced /ˈbɪpiː/) is an organic compound with the formula C₁₀H₈N₂. This colorless solid is an important isomer of the bipyridine family. It is a bidentate chelating ligand, forming complexes with many transition metals. Ruthenium complex and platinum complexes of bipy exhibit intense luminescence, which may have practical applications