Preparation of Synthetic Banana Oil Lab:

Acetic Acid + Isopentyl Alcohol ------yields----Isopentyl acetate + H20

Physical properties: Molecular wt. boiling pt density Solubility

Acetic acid 60.1 g 118 1.049 miscible

Isopentyl alcohol 88.1g 130 0.815 2.7

Isopentyl acetate (ester) 130.2 142 0.876 0.25sulfuric acid 98.1 290 1.84 miscible

150 mmol of isopentyl alcohol was used

17 mL (~300 mmol) of glacial acetic acid was used

1.0 mL of sulfuric acid was used

Exercises:

(a) Calculate the amount of isopentyl acetate that should be present in the reaction mixture at equilibrium, based on the quantities of starting materials that you used and a value of 4.2 for the equilibrium constant (Use the QUADRATIC Equation; because volumes cancel out and moles can be used in place of molar concentrations).

(b) Estimate the mass of isopentyl acetate that was lost

• as a result of incomplete reaction
• during the washings (both with 50 mL of DI water using 5% sodium bicarbonate)
• during distillation

Assume that the ester's solubility in aqueous NaHCO3 is about the same as it is in water.

Calculate the % yield?