Question

Write the following in the complex [Cr(en)₃ [CrF₆] 

(i) Type of complex 

(ii) Ligands 

(iii) central metal 

(iv) Oxidation state of central metal 

(v) IUPAC name

Answer 1

The complex [Cr(en)₃ [CrF₆]  

Cation (complex)	[Cr(en)3]3+
ligands	en - (ethylenediamine)
Name of the ligand with prefix(Ligand itself contains a Greek prefix - di, use alternate prefix)	3 ligands - prefix: tris Neutral ligand : ethane - 1,2 - diamine	tris(ethane - 1,2 - diamine)
central metal	Cr (in cationic complex)	Chromium
Oxidation state of central metal (x)	x+3 (0) = +3 x = +3	(III)
Anion (Complex)	[CrF6]3-
ligands	6F-
Name of the ligand with prefix	4 ligands - prefix: hexa Anionic ligand: Fluorido	hexafluorido
central metal	Cr (in anionic complex)	chromate
Oxidation state of central metal	x + 6 (-1) = -3 x = -3 + 6 = +3	(III)
IUPAC Name: Tris (ethane - 1,2 - diamine) chromium(III)hexafluoridochromate(III)