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Chapter 21 Notes: Transition Elements and Coordination Compounds

21.1 The Transition Metals

A. Electron Configurations of Transition Elements and Ions Ex: Write the condensed electron configurations for each of the following elements.

a. V

b. Cu

c. Cr

Ex: Write the condensed electron configurations for each of the following cations.

a. Cu+

b. Cu2+

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B. Magnetism

Ex: Are each of the following diamagnetic or paramagnetic?

a. NaCl

b. FeCl2

21.3 Coordination Compounds A. Coordination Compounds

[Co(NH3)6]Cl3 in solid and in solution

B. Types of Ligands

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Pb(EDTA)2– “At Hellmann’s, we make our mayonnaise with real, simple

ingredients like good eggs, delicious vinegar and oils rich in omega 3.”

C. Coordination Numbers

Ex: What is the coordination number of the metal ion in each of the following complex ions?

a. Zn(OH)4

2- b. Ni(en)3

2+

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D. Geometries

E. Writing Formulas of Coordination Compounds/complex ions

Examples: a. Write the formula for complex of one Ni2+ ion and four CN– ligands

b. Write the formula for the complex of one Co3+, five NH3, 1 Cl−

c. Write the formula for the bromide salt of the previous complex ion

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F. Naming Coordination Compounds/complex ions

Rules for naming:

Examples:

a. What is the name of [Ti(H2O)6](CN)3?

b. Write the formula for sodium tetrachlorocuprate(I).

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c. What is the name for [Cu(NH3)4]2+?

d. Write the formula for bisethylenediaminedichloroiron (III) phosphate

e. What is the name for [Pt(NH3)3Br]Cl?

f. Write the formula for potassium hexafluorocobaltate (III)

g. Write the name for [Fe(en)2(NO2)2]2SO4

21.4 Isomerism in Coordination Compounds

A. Structural (Constitutional) Isomers: 1. Coordination isomers:

2. Linkage isomers:

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B. Stereoisomers 1. Stereoisomers:

a. Geometric isomers (cis-trans isomers):

b. Optical isomers:

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Example: Does cis-[Co(en)2Cl2]+ have optical isomers?

Does trans-[Co(en)2Cl2]+ have optical isomers?

21.5 The Crystal Field Model

A. Introduction to the model B. Five d-orbitals in an

octahedral field of ligands

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C. Explanation of Color in Transition metal species

Example: If a solution is red, what is the color of light absorbed?

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Spectrochemical Series of Ligands

(only the top (green) line will be given on tests and quizzes) Fill in the blanks with the words longer, shorter, smaller or larger

Ex: rank the following complexes from shortest λ to longest λ of light absorbed: [Cr(en)3]3+, [Cr(OH)6]3−, [Cr(CO)6]3+

D. Magnetic Properties of Complex Ions

λ

Δ

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Lecture Example: H2O is a weak-field ligand and CN− is a strong field ligand. Draw the orbital splitting diagrams for Co3+ in Co(H2O)63+ and Co(CN)63−. Predict whether each is a high-spin or a low-spin complex.

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High and Low Spin is only applicable to d4-d7 complexes d1-d3 d8-d10

E. Splitting in other fields

d1

d2

d3

d8

d9

d10

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21.6 The Biological Importance of Coordination Complexes

Hemoglobin