Question

SAFETY NOTES: Bromobenene and acetophenone are irritants. Wear gloves and avoid contact with skin, eyes, and clothing • MHC) is dritating to the skin avoid contact with the skin, eyes, and clothing Diethyl ether, usually referred to simply as "ether", is volatile and flammable. Keep a safe distance from hot electrical devices WASTE DISPOSAL *** A itrate is the liquid that passed through the Hirsch funnel, ending up in the bottom of the sidearm Erlenmeyer flaske Take the combined aqueous solutions from the extractions and dispose of them in the aqueous Inorganic waste container. The filtrates from the crystallizations (ether) are to be placed in the flammable organic waste containers REACTIONS: OM PROCEDURE: Synthesis of phenyimagnesium bromide Assemble your glassware as soon as it is cool enough to handle without discomfort. Weigh out 75 mg of magnesium turnings (3 or 4 pieces), while wearing fresh gloves, and add them to the round- bottomed flask (RBF) along with the stir bar. Obtain 0.40 mL of ether using your plastic syringe fitted with a yellow needle. Inject the ether through the septum on the Claisen adapter. In a dry vial, prepare a solution of 0.32 ml of bromobenzene and 0.65 mL of ether using the same plastic syringe. Draw the solution into the syringe and insert it into the rubber septum of your apparatus, but DO NOT inject all of the solution. Begin stirring and inject 0.1 ml of the bromobenzene solution. Bubbles should begin to appear on the Mg surface and the solution should become cloudy when the reaction is initiated. If you do not observe this evidence after 5 minutes, warm the solution by submerging the bottom of the RBF in a beaker of warm tap water. You may also need to gently grind the Mg using a dry glass rod, and your instructor will assist you with this process. Once the reaction has begun, add the remainder of the bromobenzene solution in the syringe at a rate of 1 drop every 10 seconds. After the addition is complete, add 0.20 mL of ether to the bromobenzene vial as a rinse. Draw up the rinse solution from the vial and inject it through the septum all at once. Heat the reaction flask in a warm water bath (45-50°C) for 12 min, then cool to RT.

i need help with #3 please!

Answer 1

mmol = millimole = 10^-3 mole
weight of Mg = 75 mg volume of bromobenzene 6.3.2 m2 arolume of Aretophenone = 0.23 mL - mole of My = 75 x 10-3 g 24.3 g/mol 1 3.086 X10? more. Ma. Ni weight of bromo berzame = volume, & density. density of Bromokenzone = 1.5g/ml wtg Bromo benzemez 0:32. m2 x 1.5g/m2 0.48 g imore of Bronobenzene : 0.489 157 gimet .:.3.057 X163 mole. . - volume xdensi weight of Acetophenne = density of Aceto phenone 1.03glame wo of Ace topkuone = (0.23 X 1.0319 mole of Acetophenone a 0.23699 0.2367 9 120015gland 1.971 X10M3 mile ECS Scanned with us . CamScanner : W 15 TO241 YANG

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