有机化学实验报告模式..docVIP

有机化学实验报告2013/9/19 乙醇的蒸馏 Distillation of alcohol ●实验目的 Purpose 1. 了解用蒸馏法分离和纯化物质的原理和方法。 2. 训练蒸馏装置的安装与操作方法，要求整齐、正确。 ●实验原理 Principle Distillation has been used of centuries in the purification and separation of liquid organic substances. When the vapor pressure of the liquid being heated equals the atmospheric pressure on the surface of the liquid, it boils. The temperature, at that moment, is called boiling point. Simple distillation is a process that consists of boiling and condensing the vapor to the liquid state. Every pure organic compound has a fixed boiling point at a certain pressure. Whenever possible, simple distillation is always used to separate liquid mixtures which have boiling points more than about 30℃ apart. But sometimes an organic compound together with other components can form a binary or ternary azeotrop mixture which also has a definite boiling point. So it is difficult to say whether a liquid is a pure organic compound just based on its definite boiling point. 实验药品Materials 药品 工业酒精 用量 ●实验装置 Apparatus ①下图为常见的普通蒸馏装置图，在安装蒸馏装置的时候应该注意哪些问题？ 根据蒸馏物的量选择大小合适的蒸馏瓶，一般蒸馏物的体积应占烧瓶容量的1/3~2/3。 温度计通过木塞蒸馏头中央，其水银球上限应和蒸馏头支管的下限在同一水平线上。 蒸馏头的支管和冷凝管相连，用水冷凝时，冷凝管的外套中通水，上端的出水口应向上，可保证内套中充满水，使蒸汽在冷凝管中冷凝为液体。冷凝管的下端和接引管相连。 ②标出冷却水进出口。 ③ 为什么要加入沸石，加入沸石应注意什么问题？ 实验过程、步骤 Procedure 1.蒸馏工业酒精：如图安装蒸馏装置。为防止粘牢应在所有玻璃接头上稍稍涂上一些凡士林。注意温度计水银球的上缘应恰好位于蒸馏头侧管下缘所在的水平线上。如果不用标准磨口仪器则支管蒸馏控瓶配以合适的软木塞。 蒸馏装置装好后，将20ml工业酒精倒入50ml的蒸馏烧瓶里，然后往蒸馏烧瓶里放几根毛细管或2~3粒沸石。毛细管和沸石的作用都