Lab 7 Finding a Mechanism Laboratory Goals In this week s lab you will Propose and support a mechanistic pathway for an observed chemical reaction Safety Notes 1 The solution used this week in lab should be treated as being of unknown danger Please take all precautions to avoid getting the solution on your skin eyes or elsewhere Promptly clean any spills using plenty of water The Experiment Working with a partner your task for the lab period will be to propose a reaction mechanism for the reaction presented in lab You will have to justify your answer based upon your own experiments and observations Reaction Mechanism Reactions occur through a series of small steps that comprise what is called the reaction mechanism This series of steps explains the processes that happen as reactants react to become products You will need to be familiar and comfortable with the concept presented in section 15 6 in your textbook Kotz Treichel The success of this lab relies entirely upon you and your labmates being creative and really thinking about a reaction mechanism The LAs have been explicitly told not to tell you any answers or give you ideas regarding the mechanism of the reaction Instead their role will be to help answer any content questions that you have about mechanisms what they are why they are important etc Thus you will likely find that your best source of information is your classmates You are encouraged to work in groups and bounce ideas off each other Please be aware that you will turn in individual mechanisms with justifications The justification portion should NOT be a copy of someone else s work but rather your own understanding of why you have proposed the mechanistic steps that you have Also realize that there is no one single right answer There are many different possible correct answers Keep in mind that mechanisms can never be proven only disproven Equipment Provide You will be provided with A solution containing unknown chemicals that will undergo a chemical reaction upon shaking Access to N2 g U tubes You will also have access to the typical equipment in lab including spectrometers Your LA will also help you obtain whatever other materials that you feel may be necessary to determine the reaction mechanism though you will have to justify any requests 37 Lab Report Prior to leaving the laboratory you will be required to turn in your own lab report This lab report will contain your proposed mechanism along with the justification on why you believe that this is the best mechanism in your own words If you devise multiple possible mechanisms that can not be distinguished based on your experimentation you should include each mechanism For your mechanism s you should clearly indicate the rate limiting step as well as categorizing all the involved chemical compounds as reactants products intermediates or catalysts You should also determine your rate law for your proposed mechanism based on your assumed slow step You are encouraged to discuss your thoughts with your classmates prior to the submission of your mechanism Chemical Disposal All chemicals and solution may be disposed of down the drain with plenty of water 38