User:Douglas M. Fox/Notebook/AU CHEM-571 F2011 Lab Support/2014/10/21

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Tasklist Continue Equilibria Studies Prepare iodide ion selective electrodes Prepare 10 mL 3 M NaCl Carefully remove yellow plastic covering on Ag/AgCl electrode (as instructed) Place electrode in 15 mL falcon tube with enough NaCl solution to match volume in electrode cover and store upright until needed Prepare 50 mL 4 M KNO3 Add KNO3 to outer double junction cell, filling narrow tube + ~ 0.5 inches further Place electrode in small vial with enough KNO3 solution to cover the vycor tip Prepare 50 mL 0.01 M KI + 0.1 M KNO3 Cut a short piece (~ 3 in) of silver wire Place in KI/KNO3 solution Electrolyze the solution using the power supply The standard reduction potential for Ag/AgI is -0.15 V Oxidation occurs at the anode, which is connected to the red lead Electrolyze at low power (low current) until the wire appears coated Test your electrodes with a range of KI solutions The Ag/AgCl electrode slides inside of the KNO3 bridge solution (this is a double junction electrode) The Ag/AgI wire can be connected directly to a multimeter using alligator clips You will continue to connect your Ag wire to the red lead on the multimeter