General Properties of Transition metals

Transition metal

A metal that can form one or more stable ions with an incomplete d sub-shell

Why are Sc and Zn in d-block if they are not transition metals?

Their highest energy electron is in a d-subshell

Why are Sc and Zn not transition metals?

They do not form a stable ion with an incomplete d sub-shell

What are the 4 characteristic properties of transition metals?

• Complex formation

• Formation of coloured ions

• Variable oxidation state

• Catalytic activity

Complex

A central metal ion surrounded by ligands

Ligand

A molecule or ion that forms a co-ordinate bond with a transition metal by donating a pair of electrons

Monodentate ligands

Molecules or ions that can donate one electron pair to the central metal ion to form one co-ordinate bond

Give the 3 key examples of monodentate ligands

• Water H₂O

• Ammonia NH₃

• Chloride ion Cl^-

Bidentate ligands

Molecules or ions that can donate 2 electron pairs to the central metal ion to form 2 co-ordinate bonds

Give the 2 key examples of bidentate ligands

• 1,2-diaminoethane H₂NCH₂CH₂NH₂

• Ethanedioate ion C₂O₄^2-

Multidentate ligands

Molecules or ions that can donate more than 2 electron pairs to the central metal ion to more than form 2 co-ordinate bonds

Give the 2 key examples of multidentate ligands

• EDTA^4-

• Haem

Co-ordination number

The number of co-ordinate bonds to the metal atom or ion