tutorial 5

CHM361 Tutorial 5 Transition Metals and Coordination Compounds

Subtopic 5.1

1. Write the condensed subshell electron configuration for:a. Zrb. V3+

c. Mo3+

2. “Atomic sizes decreases at first, then becomes relatively constant.” This statement is true for trends across a period in transition metals. Explain why this is so.

3. Explain the major difference between the number of oxidation states in transition elements with the main group elements.

4. State why the oxidation state +2 is the most common among transition elements.

5. Find the oxidation numbers of the transition metal in the following compounds:a. FeCO3

b. MnO2

c. CuCl2d. Cu2(OH)3Cl

Subtopic 5.2

1. What is the meaning of coordination number for a metal ion in a complex ion? How does it differ from oxidation number?

2. What structural feature is characteristic of a chelate?

3. Name the molecular geometries associated with coordination numbers of 2, 4 and 6.

4. For each of the following ligands, determine the number and type of donor atoms in the ligand:

a. ethylenediamine (en)b. oxalate ion (C2O4

2-)c. [EDTA]4-

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5. Determine the coordination numbers of the metal ion in the following complexes:a. [Au(CN)4]-

b. [Co(NH3)4(H2O)2]Cl3c. [Au(en)2]Cl3d. [Cu(NH3)4]SO4

e. K2[Ni(CN)4]

6. Determine the oxidation numbers of the metal ion in the following complexes:a. [Cr(C2O4)3]3-

b. [Mo(en)3]3+

c. K3[Cr(CN)6]d. [PtCl4]2-

e. [Fe(H2O)5(OH)]2+

7. State the systematic name for the following compounds:a. K3[FeF6]b. Na2[CdCl4]c. [Co(NH3)4(H2O)Br]Br2

d. [Pt(en)2Br2](ClO4)2

8. Give formulas based on the following names:a. Tetraamminezinc sulfateb. Pentaamminechlorochromium(III) chloridec. Dibromobis(ethylenediamine)cobalt(III) sulfated. Potassium hexacyanoferrate(II)

Subtopic 5.3

1. For any of the following that can exist as isomers, state the type of isomerism and draw the structures:

a. [Pt(CH3NH2)2Br2]b. [Zn(H2O)(NH3)FCl]c. [Pd(CN)2(OH)2]2-

d. [Cr(NH3)5(NO2)]2+

e. [Pt(NH3)4I2]2+

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2. Determine the ligands that can form linkage isomers and explain with Lewis structures:

a. SCN-

b. S2O32-

c. HS-

3. Sketch mirror images of each of the following. From these sketches, determine whether optical isomers exist and note this fact on the drawings.

a. [Rh(en)3]3+

b. cis-[Cr(NH3)2(SCN)4]-

Subtopic 5.4

1. According to VB theory, what set of orbitals is used by a Period 4 metal ion in forming:

a. a square planar complexb. a tetrahedral complex

2. A metal ion uses d2sp3 orbitals when forming a complex. State its coordination number and shape.

3. Define crystal field theory.

4. What is crystal field splitting energy? Explain how it arises for octahedral complexes.

5. Which of these ions cannot form both high spin and low spin octahedral complexes:

a. Ti3+

b. Co2+

c. Fe2+

d. Cu2+

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6. Draw orbital energy splitting diagram and use the spectrochemical series to show the orbital occupancy for each of the following:

a. [Cr(H2O)6]3+

b. [FeF6]3-

c. [Rh(CO)6]3+

d. [Co(OH)6]4-

7. Rank the following in the order of increasing Δ and energy of light absorbed:[Cr(NH3)6]3+, [Cr(H2O)6]3+, [Cr(NO2)6]3-

8. [Cr(H2O)6]2+ is violet. Another CrL6 complex is green. Can the ligand be CN-? Can it be Cl-? Explain.

9. The tetraaquazinc(II) ion, [Zn(H2O)4]2+, is colourless. Explain why this might be expected.

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tutorial 5

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