Pre-lab 5.4.a Air-sensitive Technique for the

Safety warning Operations set off between the lines must be performed in a fume hood. 

Prepare a solution of cobalt(II) salt and electrolyte needed for maintaining ionic strength four times the concentration needed for the reaction in an Erlenmeyer flask containing a stir bar and equipped with a rubber septum and needles as above. Label Stock 2A. Purge the solution with inert gas for 5 — 10 min as in step 1. After this time, raise the tubing above the solution, allowing a slow stream of inert gas to blanket the solution [Fig. 5.2(a)]. 

Prepare a solution of ethylenediamine and acid for buffering (if appropriate) that is four times the concentration needed for the reaction in an Erlenmeyer flask equipped with a rubber septum and needles as above. Label Stock 2B. 

Purge the solution with inert gas for 5 -10 min. as in step 1. After this time, raise the tubing above the solution allowing a slow stream of inert gas to blanket the solution [Fig. 5.3(a)]. 

Using inert technique (gas tight syringe), transfer an equal volume of outflow [Co(ox)2(en)]- Stock 1 into Stock 3, while maintaining a blanket of inert gas over the reaction mixture. This is time zero for the inflow reaction. 

---