5.3.1
Transition
Elements
Section 5.3.1 covers the electron configurations of the d-block atoms and ions from scandium to zinc and the elements titanium to copper as transition elements; their variable oxidation numbers, coloured ions and catalytic behaviour; ligands, coordinate (dative covalent) bonding, coordination number and the shapes of complex ions; cis–trans and optical isomerism and the action of cis-platin; ligand substitution, including oxygen and carbon monoxide in haemoglobin; precipitation reactions with aqueous sodium hydroxide and ammonia; and the redox reactions of iron, chromium and copper, with unfamiliar reactions to interpret and predict.
Revision Notes
8 revision notes, in the order the specification teaches them.
Electron Configurations and Properties of Transition elements
Transition elements: electron configurations of d-block atoms and ions, the definition of a transition element and variable oxidation numbers.
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Ligands, Complex Ions and Their Shapes
Ligands and complex ions: coordinate (dative covalent) bonds, coordination number, bidentate and multidentate ligands and the shapes of complexes.
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Stereoisomerism in Complex Ions
Stereoisomerism in transition element complexes: cis–trans and optical isomers, including cis-platin.
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Colour of Transition element Ions
The colour of transition element ions: d-orbital splitting, absorption of visible light and the effect of oxidation number, ligand and coordination number.
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Ligand substitution and the Stability of Complexes
Ligand substitution in copper(II) and chromium(III) complexes.
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Redox Chemistry of Transition elements
Transition element redox reactions: iron, chromium and copper and colour changes.
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Reactions of Metal Ions with Sodium Hydroxide and Ammonia
Reactions of aqueous metal ions with sodium hydroxide and ammonia: precipitate colours, ionic equations and amphoteric hydroxides.
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Transition elements as Catalysts
Transition elements as catalysts: surface adsorption.
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Transition Elements Map
OCR A Level Chemistry A · 5.3.1 Transition elements and complexes
The whole section on one A4 page: transition elements, properties, ligands, shapes, stereoisomerism, cis-platin and haemoglobin.
Transition Element Reactions Map
OCR A Level Chemistry A · 5.3.1 Reactions of transition elements · 5.3.2 Qualitative analysis
The whole section on one A4 page: ligand substitution, precipitation, excess reagents, iron, chromium and copper redox, and testing for ions.
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5.3.1
- a i
the electron configuration of atoms of the d-block elements of Period 4 (Sc–Zn), given the atomic number (see also 2.2.1 d)
Revise - a ii
the electron configuration of ions of the d-block elements of Period 4 (Sc–Zn), given the atomic number and charge (see also 2.2.1 d)
Revise - b
the elements Ti–Cu as transition elements i.e. d-block elements that have an ion with an incomplete d-sub-shell
Revise - c (i)
illustration, using at least two transition elements, of the existence of more than one oxidation state for each element in its compounds (see also 5.3.1 k)
Revise - c (ii)
illustration, using at least two transition elements, of the formation of coloured ions (see also 5.3.1 h, j–k)
Revise - c (iii) a
illustration, using at least two transition elements, of the catalytic behaviour of the elements and their compounds (see 3.2.2 d)
Revise - c (iii) b
the importance of the catalytic behaviour of transition elements and their compounds in the manufacture of chemicals by industry (see 3.2.2 d)
Revise - d i
explanation and use of the term ligand in terms of coordinate (dative covalent) bonding to a metal ion or metal
Revise - e (ii) a
examples of complexes with four-fold coordination with a planar shape (see also 2.2.2 g–h)
Revise - e (ii) b
examples of complexes with four-fold coordination with a tetrahedral shape (see also 2.2.2 g–h)
Revise - f (i)
types of stereoisomerism shown by complexes, including those associated with bidentate and multidentate ligands: cis–trans isomerism e.g. Pt(NH3)2Cl2 (see also 4.1.3 c–d)
Revise - f (ii)
types of stereoisomerism shown by complexes, including those associated with bidentate and multidentate ligands: optical isomerism e.g. [Ni(NH2CH2CH2NH2)3]2+ (see also 6.2.2 c)
Revise - h (i) a
ligand substitution reactions and the accompanying colour changes in the formation of [Cu(NH3)4(H2O)2]2+ from [Cu(H2O)6]2+
Revise - h (i) b
ligand substitution reactions and the accompanying colour changes in the formation of [CuCl4]2– from [Cu(H2O)6]2+
Revise - h (ii)
ligand substitution reactions and the accompanying colour changes in the formation of [Cr(NH3)6]3+ from [Cr(H2O)6]3+ (see also 5.3.1 j)
Revise - i
explanation of the biochemical importance of iron in haemoglobin, including ligand substitution involving O2 and CO
Revise - j (i) a
precipitation reactions, including ionic equations, and the accompanying colour changes of aqueous Cu2+ with aqueous sodium hydroxide and aqueous ammonia
Revise - j (i) b
precipitation reactions, including ionic equations, and the accompanying colour changes of aqueous Fe2+ with aqueous sodium hydroxide and aqueous ammonia
Revise - j (i) c
precipitation reactions, including ionic equations, and the accompanying colour changes of aqueous Fe3+ with aqueous sodium hydroxide and aqueous ammonia
Revise - j (i) d
precipitation reactions, including ionic equations, and the accompanying colour changes of aqueous Mn2+ with aqueous sodium hydroxide and aqueous ammonia
Revise - j (i) e
precipitation reactions, including ionic equations, and the accompanying colour changes of aqueous Cr3+ with aqueous sodium hydroxide and aqueous ammonia
Revise - j (ii) a
complex formation, including ionic equations and the accompanying colour changes, with excess aqueous sodium hydroxide
Revise - j (ii) b
complex formation, including ionic equations and the accompanying colour changes, with excess aqueous ammonia
Revise - k (i)
redox reactions and accompanying colour changes for interconversions between Fe2+ and Fe3+
Revise - k (ii)
redox reactions and accompanying colour changes for interconversions between Cr3+ and Cr2O72–
Revise - k (iii) b
redox reactions and accompanying colour changes for disproportionation of Cu+ to Cu2+ and Cu
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