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9. In a 250-mL round-bottom flask, acetic acid (57 mL), 3-methylpropanol (37 g), and H₂SO4 were refluxed for 1 h. After cooling to room temperature, the reaction mixture was transferred to a separatory funnel and diluted with 200 mL Et₂0 and 200 mL cold H₂O. The organic and aqueous layers were separated. The organic layer was washed twice with 10% Na₂CO3 (aq.) The organic layer was collected and dried over anhydrous MgSO4. The mixture was filtered to remove the solids, and the crude ester was obtained by rotary evaporation of the filtrate. The product was purified by distillation and collected as the fraction that distills in the range 110-115 °C. The collected product was analyzed by GC and IR. 2-Methylpropanol MW: 74 g/mol bp= 108 °C Density=0.80 g/mL H₂SO4 reflux Acetic acid MW: 60 g/mol bp 117-118 °C Density= 1.05 g/mL + H₂O 2-Methylpropyl acetate MW: 116 g/mol bp = 118 °C Density: 0.88 g/mL 9a. (4 pts) Calculate the theoretical yield of 2-methylpropyl acetate in grams. (Show work) 9b. (4 pts) Assuming a 35% yield, what size rbf was needed for distillation (the rbf sizes are: 5 mL, 10 mL, 20 mL, 50 mL, 100 mL & 200 mL). (Show your work) 9c. (2 pts) If the major peak on this GC is the ester (bp 118 °C) product, what is the likely impurity?