UTSC - Chemistry Lab Grignard Reaction Experiment

Gather all necessary glassware including a 50 mL round bottom flask, condenser, drying tube, graduated cylinders, mortar and pestle, and pipette. Obtain dry ether, magnesium turnings, and halogen compounds as reagents.

Thoroughly clean all glassware with a test tube brush, rinse with acetone to remove water, then invert on paper towels and allow to dry for approximately 10 minutes to eliminate residual acetone.

Weigh the required mass of magnesium turnings using a weighing boat and transfer to a mortar. Thoroughly grind the magnesium with a pestle to expose more surface area for the reaction.

Using separate pipettes and graduated cylinders, prepare a feeding solution and a stock solution by combining dry ether with halogen compounds in the required amounts. Cork the graduated cylinders to prevent evaporation.

Transfer the stock solution into the round bottom flask containing ground magnesium, attach the condenser with water flow running, and start the water bath. Initiate the reaction using gentle palm heat or a warm water bath, watching for bubbling and color change to grey.

Using a fresh pipette, add the feeding solution dropwise to the self-sustaining reaction while removing and reattaching the drying tube between additions. Continue adding solution slowly until the entire feeding solution is transferred.

Allow the reaction to proceed for 10 to 15 minutes after the feeding solution is completely added. The solution should appear milky white or gray at the end. Disassemble the apparatus and allow the round bottom flask to cool at room temperature for about five minutes.