FIND PERCENT YIELD OF BENZIL Experiment 9B: Oxidation of Benzoin (Data Sheet)Running the reaction:2.50 g of benzoin and 0.39 g of tetrabutylammonium hydrogen sulfate were dissolved in45 mL ethyl acetate in a 125 mL Erlenmeyer flask19 mL of bleach, 10 m of water, and 9 mL of 0.05 M disodium hydrogenphosphate bufferwere addedThe flask was closed with parafilm and clampedThe mixture was stirred vigorously for 60 minutes during which it turned bright yellowProduct isolation:The mixture was transferred to a separatory funnel8 mL of saturated sodium bicarbonate solution were addedAfter shaking, the layers were separated (the organic layer is the top layer)The organic layer was extracted with 10 mL of waterThe layers were separated, and the organic layer was dried over anhydrous sodium sulfateThe bright yellow solution was decanted, and the drying agent was extracted with 5 mLethyl acetate; the wash was combined with the remaining organic layerUsing the rotary evaporator, the volume of the solution was reduced to 5 mLA 5.25" Pasteur pipette was filled with alumina (until 3-4 cm from the top)After wetting the column with 2 mL ethyl acetate, the concentrated solution was addedgradually; the yellow fraction was collected in a test tubeThe solvent was completely removed using the rotary evaporator leaving behind a dark-yellow semisolid5 mL of 95 % ethanol were added to the crude benzilThe mixture was heated to a gentle boil causing the solids to dissolve; the solution wastransferred to a small beakerUpon cooling to room temperature, yellow, needle-shaped crystals formed; the mixturewas placed in an ice bath for 15 minutesThe crystals were isolated by vacuum filtration using a Hirsch funnelThe crystals were washed with a small amount of ice-cold 95 % ethanol (2*1 mL)The crystals were placed in a beaker and allowed to dryProduct characterization:1.60 g of the productМ.р.: 93-95 °С

Answered: Image /qna-images/answer/d4ff810e-ee46-4cb4-b544-5815273123b6.jpg

Running the reaction: 2.50 g of benzoin and 0.39 g of tetrabutylammonium hydrogen sulfate were dissolved in 45 mL ethyl acetate in a 125 mL Erlenmeyer flask 19 mL of bleach, 10 m of water, and 9 mL of 0.05 M disodium hydrogenphosphate buffer were added The flask was closed with parafilm and clamped The mixture was stirred vigorously for 60 minutes during which it turned bright yellow Product isolation: The mixture was transferred to a senaratory funnel

Running the reaction: 2.50 g of benzoin and 0.39 g of tetrabutylammonium hydrogen sulfate were dissolved in 45 mL ethyl acetate in a 125 mL Erlenmeyer flask 19 mL of bleach, 10 m of water, and 9 mL of 0.05 M disodium hydrogenphosphate buffer were added The flask was closed with parafilm and clamped The mixture was stirred vigorously for 60 minutes during which it turned bright yellow Product isolation: The mixture was transferred to a senaratory funnel

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter16: Applications Of Neutralization Titrations

Section: Chapter Questions

Problem 16.34QAP

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