英文版实验报告

1、Preparati on of Aspiri nPurpose of experimentUn dersta nd prin ciples and methods of preparatio n of aspiri nLaboratory suppliesAcetic an hydride Salicylic acid Strong phosphoric acid Cold water IcewaterDistilled water Graduated cyli nderDryerDistillati on flasks AlcohollampTripod Asbestos n etsTher

2、mometerRubber plugsConden ser tubeRubber hose Horn tubeErlenm eyer flaskGlue applicatorBeakerFilterpaperBuchner funnelSmoke filterVacuum pump filterGlass rodsPalletscalesExperimental principle and stepsStep one :Take 20ml acetic an hydride in the dry distillatio n of the distillati onflask. Take the

3、 steam out of 138 ° c above the fractions of 6ml and the rest of thecollecti on.As Figure :-温度计c will be able toPhenomena： 136 ° c began to slip out of the liquid, to 138 collect the required fracti on.Discussi on.:New distilled acetic an hydride, as long the acetic an hydride maycontain a

4、cetic acid, will affect the resp on se. The distillati on is not using oil-bath heat ing.dry, 6ml new distilled acetic an hydride, and the n add 10 drops of concen trated phosphoricacid drops, control heating at 75° c water bath for 20 minutes.After this heat, pour the hot water 5ml, full shock

5、, then poured into the 60ml cold water, in the ice water to cool for 15 minu tes and see.Phenomena： Water-bath heating finishes, powder reaction of salicylic acid out, only to see the clarification of liquids.Cool in ice water, you can see the solution becomes a white cloudy, with sig ni fica nt cry

6、stallizati on.Chemical equati on:DiscussiOn： Concentrated phosphoric acid as a catalyst.Water-bath heating after the hot water 5ml is designed to remove excess acetic anhydride.Because the material is 0.06 mol of acetic an hydride, salicylic acid is 0.03 mol of substa nce, it is clear that acetic an

7、 hydride is excessive, so the water drop.Becomes cloudy and a large nu mber of crystallizati on, because Aspiri n builds.Step three: These turbid pour liquid as it cools in place in a Buch ner funnelfilter paper, cloth un der the funnel to pick afilter.Filter received a decompressi on filter,open de

8、compression filter switch, the pumping filter and observe.50ml distilled water wash each time, the n pump ing filter, glass rods, gen tly stirri ng con sta ntly.After you finish pump ing filter, remember to pull the rubber hose, and the n turn off the switch.Phe nomena:When the switch is open, fluid

9、 flow from the pump filter, withlarge nu mbers of crystallizati on on the filter paper in the funn el.After addi ng distilled waterwash, white cloudy smoke filtered and white Crystal precipitati on.DiscussiOn： Final analysis of the pure crystal Aspirin, Aspirin is an an ti-i nflammatory.Aspiri nsmok

10、e filters as dry as possible and avoid affecti ngexperime ntal results.Step four: Aspirin crystals after the filter using filter paper absorb, on the bala nee on the tray, called a mass of 4.2 grams.Aspirin yieldIn theory, aspiri n, salicylic acid should be equal to the amount of material gen eratedby the amount of substa nee, but the actual yield will be less tha n the theoretical yield.Las