Chemistry - Chapter 28: Transition elements

Transition element

A block d element which forms one or more stable ions with incomplete d orbitals

Ligand

A molecule/ion with one/more lone pairs of electrons which form dative covalent bonds to a central transition element atom/ion

Complex ion

A central transmission metal/ion surround by ligands, bonded to the central ion by dative covalent bond

Co-ordination number

The number of co-ordinate bonds formed by ligands

Monodentate

Ligand forming 1 co-ordinate bond with a transition element ion, using 1 lone pair of electron

Bidentate

Ligand forming 2 co-ordinate bond with a transition element ion, using 2 lone pairs of electrons

Ligand exchange

Ligands can be exchanged, wholly or partially for other ligands.

Condition for ligand exchange

New complex formed is more stable than the original complex

Degenerate orbitals

Atomic orbitals in the same energy level in a given subshell

Non-degenerate orbitals

Atomic orbitals in the same sub-shell that has slightly different amount of energy

Stability constant

Equilibrium constant for the formation of a complex ion in a solvent from its constituent ions or molecules