Inorganic Chemistry CMB004 – labs

CMB004 LABORATORY 2 Experiments, 4 Weeks on 4 th Floor Odd number locker begin with Experiment 1 Even number locker begin with Experiment 2 Group 1Weeks 1,3,5,7 (Thurs 9-1 Main Lab) All reports etc to be submitted at the end of week 8. Group 2Weeks 2,4,6,8 (Thurs 9-1 Main Lab) All reports etc to be submitted at the end of week 9. Group 3Weeks 2,4,6, 8 (Fri 9-1 Extension Lab) All reports etc to be submitted at the end of week 9.

CMB004 LABORATORY – Aims To provide training in: - A range of instrumental characterisation techniques. - Proper recording of data and observations. - The safe handling of chemicals. - Interpretation of experimental data. - Production of formal laboratory reports. - Use of common synthetic techniques. - Keeping a suitable laboratory notebook.

Experiment 1 – Cobalt(III) Ammine Complexes Synthesis – Prepare 3 Co(III) complexes Measurements – Measure UV-Vis spectra – Measure conductivity of each complex Discussion :Explain the chemistry involved in the synthesis (including equations for all the processes involved) Analyse the UV-Vis spectra and derive appropriate structural information from them Use the conductivity data to reach conclusions about the structures of the complexes Note – See appendix 1 for information about interpreting conductivity data. See lecture notes for analysis of the spectra

Experiment 2 – Synthesis and Characterisation of Nickel Complexes Synthesis – Prepare 2 nickel complexes Measurements – Measure IR spectra as KBr discs – Measure magnetic susceptibility of each complex Discussion – Explain the chemistry of the synthesis – especially any special conditions required. – Use the CHN elemental analysis data and mass spectral data to deduce the formula of each complex – Use the magnetic data to deduce the geometry and oxidation state of each complex – Use the IR data to deduce particular aspects of coordination geometry Note – Read appendices 2, 3 and 4 for information about interpreting CHN data, ESI mass spectra and magnetic data – also lecture notes.

CMB004 LABORATORY – Safety As in all laboratory courses, wearing safety glasses or other suitable eye protection is a requirement for EVERYONE in the laboratory, whether they are engaged actively in an experiment or not. You must list each hazardous compound and its hazards in your lab notebook BEFORE you begin the experiment. Every time a new compound is mentioned in the lab script, it is italicised, and is listed, along with its hazards, at the back of the lab manual. If an emergency comes up, get a demonstrator immediately. DO NOT try to handle it on your own. Eating or drinking in the laboratory is forbidden. You must wear a labcoat in the laboratory. Keep your workplace clean and tidy – leave it as you would wish to find it.

CMB004 LABORATORY – Lab notebooks The lab notebook is your record of your work – ALL work associated with the experiments. It should be possible for someone to repeat the experiment based ONLY on your notebook. You must record the date of your work, along with all observations, measurements, data and detailed calculations made as you go. All the original data, observations and calculations associated with each experiment must be in your lab notebook (including calcs done outside the lab). At the end of each lab session you must present your lab notebook to the laboratory supervisor who will initial your work (if it is satisfactory) and record your attendance at the laboratory session. The supervisor will not sign off loose pages etc. Your laboratory notebook must be handed in along with your formal laboratory reports. It will be marked independently of the formal reports. “Tidy” versions of the notebook, written after the event are not acceptable – only original versions will be marked.

A good lab notebook should score 5 on each of the points below – however they are not all equally important. cont NoPartialYes General Is this the original record ? Is all the work properly dated ? Is the record clear & easy to follow ? Was everything recorded in the notebook (no add-ins) ? Score Experimental Are relevant safety data recorded ? Is the record complete enough to repeat the experiment ? Are the masses of reactants recorded ? Are identities and volumes of solvents etc recorded ? Are reaction conditions, reflux times etc recorded ? Are observations recorded ? Score Marksheet:

NoPartialYes Data Recording Are yields (in grams) recorded ? Are masses, solvents & volumes for vis spectra recorded ? Are conductivity readings & concs recorded ? Are magnetic data (R, Ro, m, l, T) recorded ? Are appropriate significant figures and units used in weights, calcs etc? Score Calculations & Deductions Are calcs for % yield recorded ? Are calcs for conc and  recorded ? Are calcs for molar conductivity recorded ? Are calcs for magnetic moment recorded ? Are derivations of formulae of nickel complexes recorded ? Are mass spec assignment calcs recorded ? Is the type of IR spectra (KBr disks) recorded ? Are deductions/conclusions from IR data recorded? Score

CMB004 LABORATORY – Reports You will also be required to submit a formal written report for each experiment. The experimental data required to write the report should be in your laboratory notebook, however the report should be an independent and complete document – i.e. in your report you should not refer back to the notebook. The report should: - Present your laboratory work clearly, correctly and completely. - Demonstrate that you have understood the experiment and can interpret the results (showing clear reasoning) It should contain the following sections:

Abstract: One or two sentence summary of the experiment, the main results and conclusions. (This is not the same as “Aims”) Experimental: An account of the work you carried out in sufficient detail for someone to repeat it. - Be truthful. - Do not simply re-write the manual; write what you did or observed. - Do report all your observations – especially the unexpected. - Include yield, measurements made etc as appropriate.

Results and Discussion: This is the most important part of the report, carrying most of the marks – it is not sufficient to simply answer the questions in the manual. References: Give literature references for any material used. Do not copy direct from any source – this is plagarism. - Explain the chemistry behind the synthesis and measurements as fully as you can. Include equations etc as appropriate - Discuss the experimental conditions used and reasons for any special equipment or conditions employed. Comment on your yields, purity of your samples etc. If there are problems here try to suggest explanations - Interpret spectral data and other results as fully as you can – give full calculations of derived data (% yield, magnetic moment, Absorption coeff etc). In a logical sequence, explain what conclusions can be drawn from the data and use this to fully characterised the complexes.

Each report is to be written on loose A4 paper. Reports without a name on them cannot be marked; unlabelled (or incompletely labelled) samples or spectra will not be marked. You may submit reports that are either hand written or word processed, as long as they are legible. Submit samples of ALL compounds prepared. These must be properly labelled (your name, the date and the formula of the compound); these will be marked. The approximate division of marks is: Samples, spectra, other experimental data~3 marks Abstract and experimental~2 marks Derived results and discussion~5 marks Total 10 marks

TUTORIALS: There will be no timetabled tutorial sessions for this module – instead time is reserved in the lectures for problem sessions LOCKERS: You will need to get a NEW locker key You can NOT use the same locker as last year If you still have a locker key, please return it