[Co (NH₃)₅ Cl] Cl₂
First identify the positive part and name it first:
Sphere is the positive part, we will name it first. In sphere ligands are name first in alphabetical order regardless of the prefix used. So, we are having 5 Ammines (common name for ammonia as it is neutral) and one Chlorido (those ligands which contain -ve charge ends with -o). So, ammine comes first and Chlorido second,
Pentaamminechlorido
As the charge on sphere is +ve so the name of Metal will remain unchanged (i.e. Cobalt) and the oxidation state of Co is +3 so it is written in barcket and in roman. i.e.
Pentaamminechlorido cobalt (III)
At last name the negative part of complex, So,
Pentaamminechlorido cobalt (III) chloride
