General properties of transition metals transition metal characteristics of elements Ti Cu arise from an incomplete d sub-level in ions Sc 1s22s22p63s23p6 4s23d1 Ti 1s22s22p63s23p6 4s23d2 V 1s22s22p63s23p6 4s23d3 Cr 1s22s22p63s23p6 4s13d5 Mn 1s22s22p63s23p6 4s23d5 Fe 1s22s22p63s23p6 4s23d6 Co 1s22s22p63s23p6 4s23d7 Ni 1s22s22p63s23p6 4s23d8 Cu 1s22s22p63s23p6 4s13d10 Zn 1s22s22p63s23p6 4s23d10 Sc 3+ [Ar] 4s03d0 Ti 3+ [Ar] 4s03d1 V 3+ [Ar] 4s03d2 Cr 3+ [Ar] 4s03d3 Mn 2+ [Ar] 4s03d5 Fe 3+ [Ar] 4s03d5 Co 2+ [Ar] 4s03d7 Ni 2+ [Ar] 4s03d8 Cu 2+ [Ar] 4s03d9 Zn 2+ [Ar] 4s03d10 When forming ions lose 4s before 3d Why is Zn not a transition metal? Zn can only form a +2 ion. In this ion the Zn2+ has a complete d orbital and so does not meet the criteria of having an incomplete d orbital in one of its ions. these characteristics include •formation of coloured ions, •variable oxidation state •catalytic activity. •Complex ion formation, Why is Sc not a transition metal? Sc can only form a +3 ion. In this ion the Sc3+ has an empty d orbital and so does not meet the criteria of having an incomplete d orbital in one of its ions. Typical Properties of Transition metals The existence of more than one oxidation state for each element in its compounds For example iron commonly forms +2 and +3, chromium commonly forms +2,+3 and +6 see page 5 of this guide for more detail The formation of coloured ions There are characteristic colours for each transition metal element and the colours can vary in the different oxidation state. See the rest of the guide for many examples The catalytic behaviour of the elements and their compounds and their importance in the manufacture of chemicals by industry Iron is used as a catalyst in the Haber process to produce ammonia. Manganese dioxide MnO2 catalyses the decomposition of hydrogen peroxide. Vandandium pentoxide V2O5 catalyses the contact process . See 3.2.2 reaction rates for some more detail
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5.3.1 Transition elements
Properties (a) the electron configuration of atoms and ions of the d-block elements of Period 4 (Sc–Zn), given the atomic number and charge (see also 2.2.1 d) Learners should use sub-shell notation e.g. for Fe: 1s22s22p63s23p63d64s2. (b) the elements Ti–Cu as transition elements i.e. d-block elements that have an ion with an incomplete d-sub-shell (c) illustration, using at least two transition elements, of: (i) the existence of more than one oxidation state for each element in its compounds (see also 5.3.1 k) (ii) the formation of coloured ions (see also 5.3.1 h, j–k) (iii) the catalytic behaviour of the elements and their compounds and their importance in the manufacture of chemicals by industry (see 3.2.2 d) No detail of how colour arises required. Practical examples of catalytic behaviour include: Cu2+ for reaction of Zn with acids; MnO2 for decomposition of H2O2. No detail of catalytic processes required. HSW9 Benefits of reduced energy usage; risks from toxicity of many transition metals.