(a) qualitative analysis of ions on a test-tube scale: processes and techniques needed to identify the following ions in an unknown compound:

(i) anions: CO3 2–, Cl –, Br–, I–, SO4 2– (see 3.1.4 a)

(ii) cations: NH4 +; Cu2+, Fe2+, Fe3+, Mn2+, Cr3+ (see 3.1.4 a, 5.3.1 j).

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(b) the elements Ti–Cu as transition elements i.e. d-block elements that have an ion with an incomplete d-sub-shell

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(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)