Coordination Chemistry 3 Part 2 Overview Getting Started Techniques Procedure FAQ Full Lab Manual Introduction & Goals Chemistry & Background Key Questions Prelab Problems Safety Procedure In Your Write-up Experiments Index ChemLab Home		Before Lab Before coming to lab, complete the prelab portion of your write-up in your notebook. This includes the objective, reference, two prelab problems, procedure, and analysis flowchart. In your analysis flowchart, be sure to include how to draw conclusions about the mechanism of the ligand exchange reaction. The write-up for the kinetics experiments should be done separately from the acid-base titration of your complex, so start on a new page, after leaving some blank space to complete the write-up for the acid-base experiment. In Lab Record your data and observations in your notebook as you perform the experiment. Note any changes made in the procedure written in your prelab and record your observations of the reaction that occurs. Record the name of your lab partner and the source of your sample of cobalt complex. Your lab write-up should include a plot of absorbance vs. time at 500 nm and this must be completed before leaving the lab. After Lab The Results section should include • Initial absorbance of [Co(NH3)5(H2O)]3+ at 500 nm and a calculation of the extinction coefficient at this wavelength, using Beer's Law. • Your measurements of absorbance vs. time at 500 nm . Your Discussion should explain the observed change in absorbance vs. time at 500 nm, by postulating a mechanism for the reaction. Include a discussion of which isomer of the NO2- ligand is observed first, which is formed later, the relative rates of the first and second reactions, and finally, how your data support this hypothesis.
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