Q. Which one of the following metal complexes is most stable?
Solution:
Complex $\left[ Co (e n)_{3}\right] Cl _{2}$ is most stable complex among the given complex compounds because more number of chelate rings are present in this complex as compare to others.
1
$\left[ Co ( en )\left( NH _{3}\right)_{4}\right] Cl _{2}$
1 chelate ring
2
$\left[ Co (e n)_{3}\right] Cl _{2}$
3 chelate ring
3
$\left[ Co ( en )_{2}\left( NH _{3}\right)_{2}\right] Cl _{2}$
2 chelate ring
4
$\left[ Co \left( NH _{3}\right)_{6}\right] Cl _{2}$
0 chelate ring
| 1 | $\left[ Co ( en )\left( NH _{3}\right)_{4}\right] Cl _{2}$ | 1 chelate ring |
| 2 | $\left[ Co (e n)_{3}\right] Cl _{2}$ | 3 chelate ring |
| 3 | $\left[ Co ( en )_{2}\left( NH _{3}\right)_{2}\right] Cl _{2}$ | 2 chelate ring |
| 4 | $\left[ Co \left( NH _{3}\right)_{6}\right] Cl _{2}$ | 0 chelate ring |