Question

I did an experiment where I synthesized 2-phenyl-2-propanol using the grignard reaction. please help me answer these lab questions

Reagents Moles of Reagent 0.00142 moles (0.224 g)bromobenzene 0.00712 mol (0.173 g) 2 mL of THF (n/a moles) tetrahydrofuran 0.00142 mol (0.083g, 0.11mL) acetone, HPLC grade, anh Reagent Name FW 157.75 24.31 n/a 58 Comments Mg powder grind before using must be anhydrous must be anhydrous Pre-Lab Assignment: 1. Determine the volume (mL) of bromobenzene needed for the experiment. Obtain the density information from the MSDS 2. Determine the Skin LD, for bromobenzene and report the species tested. 3. Determine the Skin LD, for tetrahydrofuran and report the species tested. 4. Determine the Skin LD, for acetone and report the species tested. 5. What other hazards exist in this lab? 6. D etermine the limiting reagent for the experiment, determine the theoretical yield of 2-phenyl-2- propanol based on starting reactant amounts. Questions: Answer the questions on this section to make sure you understood the concepts of this lab. These questions will not be graded, but answering them will help you prepare for the lab quiz you will take during in a later lab period. I. What was the reaction yield (in grams)? What is the % yield for your reaction? 2. Was benzene present as a side product in the GC? If so, try to identify it (there is likely for comparison in our lab facility because of benzene's toxicity. no standard 10 3. What steps were taken to keep the system water free? Name each precaution taken. 139 Chem 421, Experiment #8 Experiment 8 The Grignard Reaction used in the Synthesis of 2-PhenyL-2-Propanol Objective: To synthesize 2-phenyl-2-propanol using the Grignard reaction. Background: This laboratory exercise introduces the student to the Grignard reaction in the synthesis of a 3" alcohol, 2-phenyl-2-propanol. но 1. Mg /THF / heat 2. acetone 3. dilute acid quench Br It is expected you have a solid understanding of all the work-up and purification procedures used in this experiment. You should refer to the appendix of this lab manual and read the sections on boiling point/distillation theory, IR theory, and gas-chromatography if you need a review. Cen This reaction is performed in the hood because flammable solvents are used. You must show up to class on time since all students will be starting together and need to link their water hoses together Students arriving late will not be permitted to perform this lab and will forfeit the points. Wet glassware will interfere with this reaction. If you did not clean your glassware during lab last time, you will need to clean it now, and exchange it for dry glassware from the stockroom. You need to get through step 35 of this experiment on the first day. Safety: Warning: this lab uses tetrahydrofuran; an extremely volatile and flammable solvent absolutely no flames during this reaction. Consult the MSDS binders in the lab for information on the chemicals if you have concerns. MSDS information is also available on the internet.

Answer 1

ns: 그, O 222 S7.7S o 185 193 X/JD = 95.85%