ChemistryCode 9701
General characteristic chemical properties of the first set of transition elements, titanium to copper
What this topic asks you to be able to do
- describe and explain how transition elements react with ligands to give complexes, including those of copper(II) and cobalt(II) ions formed from water and ammonia molecules, or from hydroxide and chloride ions
- define a ligand as any species with a lone pair of electrons which it uses to form a dative covalent bond with a metal atom/ion at the centre
- understand these kinds of ligand, including the examples given, and use the terms: (a) monodentate ligands, such as H2O, NH3, Cl– and CN– (b) bidentate ligands, such as 1,2-diaminoethane, en, H2NCH2CH2NH2, and the ethanedioate ion, C2O42– (c) polydentate ligands, such as EDTA4–
- define a complex as a molecule or ion made up of a metal atom or ion at the centre, bonded to one or more ligands
- describe the shape and bond angles (the geometry) of linear, square planar, tetrahedral and octahedral complexes of transition elements
- state the meaning of coordination number (b) predict a complex ion's formula and charge from the metal ion, the charge or oxidation state of that ion, the ligand, and either the coordination number or the geometry
- account for, in qualitative terms, the fact that ligand exchange may take place, including for copper(II) and cobalt(II) ions when combined with water molecules, ammonia molecules, hydroxide ions and chloride ions
- predict, with the help of E⦵ values, whether redox reactions involving transition elements and their ions are feasible
- describe the reactions of the following, and carry out calculations on them when suitable data are given: (a) MnO4–/C2O42– in acid solution (b) MnO4–/Fe2+ in acid solution (c) Cu2+ / I–
- use the data provided to carry out calculations on further redox systems