Coordination compound
source : prenhall.com
Rules for preparing formula of Coordination compound from IUPAC name:
1)Formula of cation whether simple or complex is mentioned first, followed by that anion.
2) Coordination sphere is kept into square bracket.
3) Symbols present in coordination sphere are – Metal atom or ion , anionic ligands, neutral ligands & cationic ligands.
4) If there are more than one ligand of any type is present then number 2,3,4 etc. is used to indicate the number of ligands.
5) The charge on complex ion can be calculated after knowing the charge carried by each ion.
x = oxidation state of metal + Algebric sum of the charges present on all ligands.
Ex.1 ) Tetra amine chloro nitro Cobalt (III) nitrate
Anion – NO3–
Cation – [Co Cl (NO2) (NH3)4]x
x = oxidation number of Co + oxidation number of Cl + oxidation number of NO2 + 4 x oxidation number of NH3
= 3 +1 (-1) +1(-1) +4 x 0
x = +1
Complex cation- [Co Cl (NO2) (NH3)4]+
Complex compound – [Co Cl (NO2) (NH3)4] NO3
Ex.2 ) Hexa aqua Iron (II) sulphate
Anion – SO42-
Cation – [Fe (H2O)6]x
x = oxidation number of Fe + 4 x oxidation number of H2O
= 2 +6 x 0
x = +2
Complex cation- [Fe (H2O)6]++
Complex compound – [Fe (H2O)6]SO4
Ex.3 ) Penta amine Nitrito Cobalt (III) chloride
Anion – Cl–
Cation – [Co (ONO) (NH3)5]x
x = oxidation number of Co + oxidation number of ( ONO) + 5 x oxidation number of NH3
= 3 +1 (-1) + 5 x 0
x = +2
Complex cation- [Co (ONO) (NH3)5]++
Complex compound – [Co (ONO) (NH3)5] Cl2
Ex.4 ) Tetra aqua oxalato Iron (III) chloride
Anion – Cl–
Cation – [Fe (H2O)4 (C2O4]x
x = oxidation number of Fe + 4 x oxidation number of H2O + oxidation number of C2O4
= 3 +4 x 0 +1 (-2)
x = +1
Complex cation- [Fe (H2O)4 (C2O4]+
Complex compound – [Fe (H2O)4 (C2O4]Cl
Ex.5 ) Potassium hexacyano Ferrate (II)
Anion – [ Fe (CN)6]x
Cation – K+
x = oxidation number of Fe + 6 x oxidation number of CN
= 2 + 6 (-1)
x = -4
Complex anion – [ Fe (CN)6]4-
Complex compound – K4 [ Fe (CN)6]
