1. Chapter 8 Worked Example 1 The decavanadate ion is a complex species with chemical formula V 10 O 28 6-. It reacts with an excess of acid to form the dioxovanadium ion VO 2 +, and water. Write a balanced equation and state the oxidation state of vanadium before and after reaction. Which vanadium oxide has the same oxidation state of V? Solution V 10 O 28 6- + 16H + 10 VO 2 + + 8H 2 O Oxidation state of V in both species is +5 {V(V)} V 2 O 5 is the V(V) oxide

2. Chapter 8 Worked Example 2 Determine the oxidation state of the metal in each of the Following coordination complexes: [V(NH 3 ) 4 Cl 2 ], [Mo 2 Cl 8 ] 4-, [Co(H 2 O) 2 NH 3 Cl 3 ] -, [Ni(CO) 4 ] Solutions [V(NH 3 ) 4 Cl 2 ] [Mo 2 Cl 8 ] 4- [Co(H 2 O) 2 NH 3 Cl 3 ] - [Ni(CO) 4 ] V = +2 Mo = +2 Co = +2 Ni = 0

3. Chapter 8 Worked Example 3 Give the chemical formula that corresponds to each of the following compounds. (a)Sodium tetrahydroxozincate (II) (b)Dichlorobis(ethylenediamine)cobalt(III) nitrate (c)Triaquabromoplatinum (II) chloride (d)Tetra-amminedinitroplatinum (IV) bromide Solutions

4. Chapter 8 Worked Example 4 Determine the oxidation state of Mn in the following oxides and oxoanion. MnO MnO 2 Mn 2 O 3 Mn 2 O 7 Mn 3 O 4 [MnO 4 ] - Solutions +2 +4 +3 +7 +2, +3 +7 MnO MnO 2 Mn 2 O 3 Mn 2 O 7 Mn 3 O 4 [MnO 4 ] -

5. Chapter 8 Worked Example 5 Draw the structures of all possible isomers for the following complexes. Indicate which isomers are enantiomeric pairs. (a)Diamminebromochloroplatinum(II) (square planar) (b)Diaquachlorotricyanocobaltate(III) ion (octahedral) (c)Trioxalatovanadate(III) ion (octahedral) Solutions

7. Chapter 8 Worked Example 6 (a) Explain why octahedral complexes with three and eight d electrons on the central metal atom are particularly stable. (b) Explain under what circumstances you would expect octahedral complexes with five or six d electrons on the central metal atom to be particularly stable. Solutions

9. Chapter 8 Worked Example 7 The three complex ions [Mn(CN) 6 ] 5-, [Mn(CN) 6 ] 4-, and [Mn(CN) 6 ] 3- have all been synthesized and are all low-spin octahedral complexes. For each complex ion, determine the oxidation number of Mn, the configuration of the d-electrons (how many t 2g and how many e g ), and the number of unpaired electrons. Solution

10. Chapter 8 Worked Example 8 Three different compounds are known to have the empirical formula CrCl 3.6H 2 O. When exposed to a dehydrating agent, compound 1 (dark green) loses 2 mol water per mol of compound, compound 2 (light green) loses 1 mol water and compound 3 (violet) loses no water. Solution Water of hydration is much easier to remove than water ligands: Compound 1 is [Cr(H 2 O) 4 Cl 2 ]Cl.2H 2 O Compound 2 is [Cr(H 2 O) 5 Cl]Cl 2.H 2 O Compound 3 is [Cr(H 2 O) 6 ]Cl 3