英文版化学实验报告由刀豆文库小编整理，希望给你工作、学习、生活带来方便，猜你可能喜欢“英文版化学实验报告”。
Preparation of Ethyl Acetate
I.Experimental Objective
1.To grasp the esterification reaction principle and methods of preparation of ethyl acetate from acetic acid and ethanol.2.To learn to reflow method on the reaction.3.To review the use of distillation, separating funnel, basic operations, such as washing and drying of the liquid.II.Principle of the Test
This experiment regarded glacial acetic acid and ethanol as raw material, it adopted the ethanol overdose and the suction effect of concentrated sulfuric acid to make the reaction goes smoothly.In addition to generating the main reaction of ethyl acetate, there is generated a side reaction of diethyl ether.Primary reactions:
CHCHCHCOOH323+浓HSO24
HOCHCOOCHCH2323+
Side reactions:
CHCH32浓HSO170 CoHHC22O+H2
2(CHCH)322浓HSO140 oC(CHCH)O322HO2+
III.Apparatus and Reagents
Apparatus: 100ml round-bottomed flasks, condenser tubes, thermometers, funnels, electric sets, still, adaptor, metal stand, rubber tubes beakers.Reagents: ethanol，acetic acid，sulfuric acid magnesium，sodium carbonate，salt，calcium chloride，concentrated sulfuric acidIV.Experiment procedure
1, Put 3 mL(0.052 mol)acetic acid and 5 mL(0.086 mol)ethanol into a 100 mL flask, then 1.3mL of concentrated sulfuric acid was placed into it with shaking , placed the flask into a magnetic stirred and heated to reflux for 1 hour.Finally, cooled it to room temperature.2, Add water, stirring until the solids fully diolved, then transferred it to a separatory funnel, shaking and pointing to the water-course.3, The organic layer was washed with saturated brine, a saturated sodium carbonate solution, 3mL each sufficiently washed with water , followed by washing with a saturated solution of calcium chloride 3mL, anhydrous calcium sulfate 20 min.4, Filtered it into 50 mL flask, a distillation apparatus and heated distillation, collecting the fraction 73-78 ℃.Weighed to calculate the yield of the measured refractive index product.V.Data Proceing
Final amount of ethyl acetate was 1.8g.(Acetic acid relative molecular ma 60.05
Density 1.049)(relative molecular ma of 88.12 acetate relative density 0.905)
Yield = 1.8 /(0.052x88.12)X100% = 39.1%
VI.Attention
1.When adding concentrated sulfuric acid exothermic, should be added slowly with shaking.2.Drying should be stuffed with cork and intermittent oscillation
3.In addition to the distillate ester and water, but also contains small amounts of unreacted acetic acid and ethanol, and diethyl ether containing byproducts.It must be removed with a base wherein the acid and the unreacted alcohol was removed with a saturated solution of calcium chloride, which could affect the yield of ester.4.When making the next wash, sodium carbonate must wash away, or when the alcohol wash with saturated solution of calcium chloride, calcium carbonate will produce flocculent precipitate, resulting in the separation difficult.
