Transition metals

• Transition metals


  1. block elements that gain at least one stable ion with a partially filled d-subshell
• Transition metals


  • Can form complex ions
  • Can form coloured ions
  • Are good catalysts
  • Can exist in variable oxidation states
• Transition metal ions


  • Fe2+
  • Fe3+
• Transition metals form positive ions
• Non-transition metals do not have a partially filled d-subshell as their ground state
• Non-transition metal ions


  • Sc++
  • Zn2+
• Coordination number


  Number of coordinate bonds formed with the central metal ion
• Coordination numbers


  • 4
  • 6
• Monodentate ligand


  Ligand that donates one pair of electrons to form one coordinate bond
• Bidentate ligand


  Ligand that donates two pairs of electrons to form two coordinate bonds
• Multidentate ligand


  Ligand that donates more than one pair of electrons to form more than one coordinate bond
• Multidentate ligand


  • EDTA
• Ligands donate electrons to the central metal ion to form coordinate bonds
• Coordinate bonds are formed by the donation of electron pairs
• Transition metal complexes have a defined coordination number and geometry
• Octahedral and tetrahedral are common complex ion geometries
• Isomerism can occur in complex ions
• Optical isomerism and cis-trans isomerism can occur in complex ions
• Binding of ligands to DNA can disrupt DNA and prevent cancer cell division
• Transition metal compounds can be oxidizing agents because they readily lose electrons to form positive ions (cations).
• The transition elements are the d-block elements, which have partially filled or completely filled d orbitals.
• The ability of transition metal ions to accept electrons makes them useful as reducing agents.