(a) The reaction scheme shows some reactions of [Co(H2O)6]2+. [Figure 3.0]

1. (a)(i)Write the formulae of the following species. A B[2]
2. (a)(ii)State a suitable reagent for reaction 1.[1]
3. (a)(iii)Write an equation for reaction 2.[1]
4. (a)(iv)Write an ionic equation for reaction 3.[1]
5. (b)Co2+ ions catalyse the oxidation of 2,3-dihydroxybutanedioate ions, C4H4O6²¯, to methanoate ions, HCO2, carbon dioxide and water.
6. (b)(i)What property of transition elements allows Co2+ ions to act as a catalyst?[1]
7. (b)(ii)Draw the structure of the 2,3-dihydroxybutanedioate ion.[1]
8. (b)(iii)Complete the equation for the oxidation of 2,3-dihydroxybutanedioate. Use [O] for the oxidising agent in this reaction. C4H4O6²¯ +[1]
9. (c)Platin, Pt(NH3)2Cl2, displays cis-trans isomerism.
10. (c)(i)Draw the structures of these isomers. cis isomer | trans isomer[2]
11. (c)(ii)Cis-platin is an effective anti-cancer drug. Describe the action of cis-platin in this role.[2]
12. (d)The use of cis-platin can cause side effects so carboplatin has been developed. Carboplatin can be synthesised from cis-platin, Pt(NH3)2Cl2, by replacing the two chloride ion ligands with a single cyclobutane-1,1-dicarboxylate ion ligand as shown. [Figure 3.1] Suggest the structure for carboplatin and draw it in the box.[1]

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