CH3201: Reactivity and Properties of the Elements and their Compounds

School Cardiff School of Chemistry
Department Code CHEMY
Module Code CH3201
External Subject Code 101043
Number of Credits 20
Level L5
Language of Delivery English
Module Leader Dr Angelo Amoroso
Semester Double Semester
Academic Year 2013/4

Outline Description of Module

This module builds on the knowledge, understanding and skills acquired by successful completion of the Year 1 module CH3102, to explore further the chemistry of main group and transition elements.  Trends in the behaviour of the p-block elements and their compounds are considered, with particular focus on the inert pair effect, the role of d-orbitals, p-bonding, and structure and bonding in “electron-deficient’ compounds.  The mechanisms of substitution and redox reactions of transition metal complexes are described.  Trends in reactivity and magnetic properties are explained in terms of ligand field theory.

On completion of the module a student should be able to

  1. explain the anomalous behaviour of first row main group elements;
  2. explain and predict the strength and stability of p-bonding in the main group compounds;
  3. discuss and comment on the role of d-orbitals in bonding in main group compounds;
  4. summarise the periodic trends in reactivity and structure within the s- and p-blocks;
  5. understand the origin and occurrence of the inert pair effect;
  6. discuss the reactivity of the noble gases;
  7. explain the nature of orbital overlap within the double bonded Group 14 compounds;
  8. recall synthetic routes to boranes and carboranes and be aware of their reactivity;
  9. understand and implement Wade’s rules;
  10. recall the general reactions utilised in the synthesis of main group metal-alkyl species;
  11. discuss the structure and bonding in main group metal-alkyl and metal-hydride species;
  12. explain trends in the reaction rates of transition metal complexes;
  13. recall basic substitution mechanisms of metal complexes, as well as mechanisms for rearrangement;
  14. discuss substitution pathways for square planar complexes;
  15. understand, and implement in the design of synthetic procedures, the trans effect and the trans influence;
  16. describe the mechanisms by which electron transfer can occur;
  17. identify likely electron transfer mechanisms for a given complex;
  18. explain/predict substitution pathways for typical substitutionally inert complexes;
  19. identify magnetic behaviour by the variation of the magnetic susceptibility with temperature;
  20. discuss the relationship between the magnetic susceptibility and the magnetic moment;
  21. predict the orbital contribution for a given dn configuration;
  22. predict the temperature dependence of an orbital contribution;
  23. predict the occurrence and magnitude of Jahn-Teller distortions in transition metal complexes;
  24. explain the relative preferences for low or high spin configurations in d4-7 complexes;
  25. identify HS-LS equilibria and explain the nature of a given equilibrium;
  26. relate the roles of solvation and coordination environment in stabilising metal and non-metal species;
  27. write out the periodic table, excluding lanthanides and actinides;
  28. understand the origins of the spectrochemical series and how to, from first principles, to place an unseen ligand within the series;
  29. count electrons and derive electron configurations for transition metal complexes and organometallics in weak/strong field cases;
  30. correlate spectra of transition metal complexes to symmetry and d-electron configuration;
  31. understand the effects of crystal field stabilisation energy on the kinetic and thermodynamic properties of complex ions;
  32. understand qualitatively the thermodynamics and kinetics of reactions of metal-ligand complexes.
  33. understand experimental methods for the investigation of reaction mechanisms and interpret experimental data.

How the module will be delivered

33 1-hour lectures, 30 hours of practical work (6 3-hour sessions and 3 4-hour sessions), 4 1-hour workshops, 4 tutorials

Skills that will be practised and developed

On completion of the module a student will be able to:

  1. rationalise trends in chemical properties within/across groups in terms of electronic and atomic properties;
  2. evaluate the roles of π-bonding, inert pair effect, and variations in overlap and bond strength in influencing properties;
  3. identify characteristic structural building blocks of extended structures and relate these to stoichiometry and physical properties;
  4. predict the structures and properties of yet unseen cluster molecules based on electron counting;
  5. interpret NMR spectra (diamagnetics and paramagnetics) for main group, transition metal complexes and organometallics;
  6. summarise key features of the chemistry of main group elements and account for these in terms of atomic properties;
  7. derive – in crystal field terms – orbital energy diagrams of tetrahedral and square planar complexes;
  8. derive and interpret MO diagrams for octahedral complexes and related organometallics.
  9. quantitatively determine an overall stability constant from stepwise constants, and interpret stability constant data;
  10. interpret physical measurements, derive key kinetic and thermodynamic parameters and comment upon the significance of the results;
  11. interpret ligand field spectra in terms of ligand field parameters, complex geometry and selection rules;
  12. interpret magnetic data of unknowns, and suggest identities which explain the observed behaviour.

How the module will be assessed

A written exam (3 h) will test the student’s knowledge and understanding as elaborated under the learning outcomes. The coursework (workshops and tutorials) will allow the student to demonstrate his/her ability to judge and critically review relevant information.  Practical skills will be assessed via a series of laboratory-based exercises.

Assessment Breakdown

Type % Title Duration(hrs)
Exam - Spring Semester 50 Reactivity And Properties Of The Elements And Their Compounds 3
Practical-Based Assessment 25 Practical Work N/A
Written Assessment 25 Workshops And Tutorials N/A

Syllabus content

Main group chemistry (Autumn semester)

Anomalous behaviour of 1st element in each group: pπ-pπ bonding; interelectronic repulsion; role of d-orbitals; hypervalency; dπ-pπ bonding

Chemistry of the p-block elements (Groups 13-18): systematic survey; inert pair effect; ionic vs. covalent; trends in reactivity and structure of halides; hydrides; oxides/oxoanions; borazine & phosphazene; noble gas chemistry; multiple bonding between heavier main group elements (disilenes, distannenes, etc)

Electron-deficient compounds: diborane, Wade’s rules, carboranes, other main group clusters

Organometallic chemistry of main group elements (s- & p-block): synthesis, reactivity, structure and bonding

 

Coordination chemistry (Spring semester)

Mechanisms of reactions of metal complexes

Trends in reaction rates as a function of periodicity. Electronic influences on rates.

Fundamental mechanistic types – associative, dissociative, interchange.

Determination of mechanisms, fundamental rate equation, thermodynamic parameters, dependence on pressure, stereochemical studies, labelling studies.

Other mechanisms – Bailar twist, conjugate base mechanism.

Ligand influences on reactivity of coordination complexes in aqueous solution: p-base/p-acid ligands.

Reaction mechanisms in square planar complexes, dual pathway mechanism.

Trans effect and trans influence. Werner’s studies on square planar complexes.

Oxidation reduction reactions, inner sphere and outer sphere mechanisms.

Principle of microscopic reversibility.

Magnetochemistry

Classical descriptions/definitions: diamagnetism, paramagnetism, ferromagnetism, antiferromagnetism, antiferrimagnetism (and related variations)

Relationships between T, chi and mu for various cases.

Langevin equation and measuring chi and mu: theory and practice

Van Vleck equation and the spin only formula

Magnetic moments (S+L)

Jahn-Teller effect  (tetragonal and trigonal) – structural and spectroscopic implications

High spin-low spin equilibria; HS-LS preferences for d4 vs d5 vs d6 vs d7

Essential Reading and Resource List

An indicative reading list will be included in the Course Handbook.


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