Topic 5.2 Transition Metal Chemistry

5.2a derive the electronic configurations of atoms of the d-block elements (Sc to Zn), and their simple ions, from their position in the Periodic Table

5.2b recall the transition metals as d-block elements forming one or more stable ions which have incompletely filled d-orbitals
Students should be able to recall appropriate parts of the chemistry of chromium, iron and copper to illustrate the properties of transition elements described in c, d and e.

5.2c recall the characteristic properties of the transition elements, such as
(i) the formation of coloured aqueous ions, and other complex ions
(ii) the formation of a range of compounds in which they are present in different stable oxidation states

5.2d understand the nature of the bonding in complex ions, including the aqua-ions, their shape and the cause of their colour
· stereoisomerism in such complex ions will not be examined
· an elementary treatment only is required. Students should understand that the bonding between the ligand and the metal ion is dative covalent and this causes a splitting of the D-orbitals
· colour should be related to a simple transfer of electrons between D-orbitals.

5.2e understand simple ligand exchange processes

5.2f recall the formation of hydroxide precipitates on the addition of aqueous solutions of sodium hydroxide or ammonia, and that some hydroxide precipitates react with an excess of strong alkali, and some react with an excess of ammonia; limited to Cr³⁺, Mn²⁺, Fe²⁺, Fe³⁺,Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺
· students will be expected to recall the colours of the hydroxide precipitates and the colours of complexes formed in excess alkali and ammonia
· the concepts of deprotonation and ligand exchange should be applied to these reactions

5.2g recall the oxidation states of vanadium (+2, +3, +4, +5) in its compounds, and deduce, given E^o values, reagents for the interconversion of the metal ions, oxo anions and oxo cations of the element in these oxidation states
· students will be expected to recall the colours of the aqueous solutions of vanadium compounds in the oxidation states listed above

5.2h describe reactions for the interconversion of the oxidation states of vanadium in aqueous solution