Question

calculate the % yield fir the n-butylacetate synthesis. show how you obtained expected yield.

Mass of final product was 3.4g

INSTRUCTIONS A. SETTING UP THE EXPERIMENT This wetion was completed during Experiment D. Proceed to Part B. anol) and 0.75 mL concentrated H2SO4 1. GOGGLES AND GLOVES. Carefully pour the following materials into a flask: 5 ml glacial acetic acid, 4.5 mLn-butanol (1-butanol) and 0.75 ml 2. Swirl carefully to mix the components thoroughly. 3. Seal the flask well (cork & Parafilm), label it properly and leave it in for two weeks. no heating will be required. d leave it in for two weeks. If this is done, B. PURIFICATION hich has been transferred IN THE FUME supper in the thermometer position". Set heating 1. Add a few boiling chips to the esterification mixture which has been transferred HOOD wearing gloves to a 50 mL round bottom flask and subject it to distillation using mantel. Instead of a thermometer, put a glass stopper in the thermometer position mantel to 8. 4 Heat continuously and distil rapidly into a 50 mL round bottom flask until only about 1-2 of dark residue is left in the original round bottom flask. DO NOT go to dryness as the is very difficult to clean. 3. Allow the distilling flask to cool before disconnecting it from the condenser. IF THE FI STILL HOT, IT WILL GIVE OFF PUNGENT FUMES - BE CAREFUL NOT TO INHALE THESE. Keep the stopper on for as long as possible. 4. Waste: Pour any dark residuc into the "ORGANIC WASTE" bottle and rinse the flask with small amounts of water from a wash bottle IN THE FUME HOOD. If required, clean the charred flask with dry Cow Brand NaHCO3, a brush and lots of L-BO grease. C. WASHING 1. IN THE FUME HOOD and wearing gloves, pour the acidic distillate into a sep funnel and slowly add about 13 mL of saturated Na:CO3. Foaming will occur. 2. Gently swirl the funnel in an upright position to mix the layers without the stopper (otherwise the stopper will fly off). 3. When the foaming has subsided (it doesn't have to stop completely), put in the stopper and carefully invert & shake, relieving pressure through the stopegck 4. Keep swirling until most of the pressure has dissipated. 5. Check whether the acid has been neutralized by running a drop of the water layer out of the funnel onto a piece of litmus paper (red = acidic, blue = basic). If necessary, add more saturated carbonate to complete the neutralization. 6. Waste: Discard the water layer in the sink, flushing with tap water.

Answer 1

Answers :- 17 yield for n-butylacerate = 59.65 % Expected yield -,5.70 g Explanation Let us draw the Reaction scheme for n-butyl acetate synthesis using i-butanol and glacial acetic acid MOH + HELLOH a noi tho n-butanol n-butylacetate Mw=74.123 gomolt a MW = 116.16 gomol! we calculated mass of n-butanol = 3.645 g, calculated by using density value and volume of n-butanol density of n-butanol = 0.81 g/m2 (standard) -value volume of n-butanol = 4.5 mL mass (g) Density = volume to => mass = 0.81 g/mol X 45 myl n-butanol mass = 3.645 g huranos morarmass = 74.123 gomolt " Number of moles of n-butanol = 3.645 g 74.123ginal- = 0.049 1 mole

1 Value Given that we wed 5mb of glacial acetic and - which has 0.0874 moles of CH₃COOH - mass of glacial, acetic and is calculated by knowing the density of glacial acetic acid = 1.05 g/m mass of glacial acetic acid = 5 mx 1.05 g/mL (standard) - mass of ghcial acetica id= 5:25g 1 l mw of glacial .: moles = 50259 acetic and 60.052 gomol = 60.052 gomot moles of glacial - acetic acid =0.0874 mole • since the n-butanol has less number of moles than the glacial acetic acid, the limiting reactant will be n-but and Now Let us calculate expected xield of n-butyl- acetate synthesis. Expected yield = Moles of Limiting x molar mass of Reactant nobutylacetate = 0.0491 mete x 116.16 gomple! = 5.70 g Expected yield

But the mass of the final productie in-butyl- acetate = 3.4 g (Actual yield) actual yield x 100% :: 0% yield = Expected yield 3.4 g 4100% 5.70.gr % yield = 59.65 %