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沸点测定器

*通信:

詹妮弗•斯图尔特
澳大利亚堪培拉大学化学工程学院
电子邮件: (电子邮件保护)

文摘

这里描述的装置更易于确定的样本的典型的沸点大约三分之一ml.任何液体,不攻击汞或玻璃,在30°C到200°C。没有大气压力的变化来计算修正或紧急测温列,过热并不是必要的,因为这种方法是静态的。操作快速,设备容易使用,清洁,和费用。这种方法可以用来找到期间变化成分的混合物的沸点蒸馏一样容易它可以用来估算纯液体或共沸混合物的沸点。

介绍

现在的设备的精度为0. l°C。它是由一个玻璃u形管7毫米直径孔和长肢约150毫米;越短肢长约90毫米,可以关闭一个磨砂玻璃塞p .汞杯M是环绕插头。从曲线附近的基准线,四肢都是毕业于毫米。汞是放入干净、干燥管塞P后删除。在苏格兰glak韩国大学在悉尼,澳大利亚新南威尔士州。四肢垂直时,汞被添加,直到达到在短肢的规模。时间越长肢是配备了一个橡皮管,另一端连接到一个开关,灯泡的压力。水星在短肢被迫增加工作中的灯泡和活塞,直到大约2毫米的地面灯插头插座。水星在短肢,约三分之一ml.液体的沸点是确定倒。 A pipet is used to remove any air bubbles that have adhered to the mercury or glass. The glass plug is inserted into its socket, taking care not to trap any air. The plug is held in place by springs or a rubber hand attached to the plug and mercury cup's horns. The rubber tube is then removed from the longer limh and mercury is poured into the mercury cup to seal the plug. The charged U-tube is clamped vertically in a large beaker containing a transparent liquid with a high boiling point, such as medical parah. A tiny plumbline is lowered down the longer limb to confirm verticality of the limbs. The bulb of a short-stem thermometer calibrated for total immersion is clamped towards the middle of the scale on the shorter limb, and the graduation reflecting the sample's expected boiling point is immersed in the bath liquid. The beaker is heated by placing it on an asbestos pad with a central hole where a flame may be seen immediately on the beaker's bottom. The bath water is constantly churned by raising and lowering a huge annular metal stirrer mechanically or manually. At sea-level, the barometric height is measured and converted to an equivalent column of ice-cold mercury.

半月板的四肢都读;就没有任何区别了汽化是否已经开始。我们称这些读数a和b毫米。毕业的最低的规模等于0。当有温度达到沸点样本的预期,调整火焰,使浴温度上升不超过每分钟0.5”。当样品达到沸点时,它开始蒸发,下面的汞抑郁,导致汞在更长的肢体上升。当水星在更长的肢体达到毕业提供的公式(H + a + b - 760)毫米,读取温度计由于汞含量的差异。是这样的,它可以弥补H的变化从760毫米,然后样本的蒸汽压力是760毫米。火焰是略有变化,所以,它不直接通过孔中间的石棉垫,地毯,因此温度缓慢下降。冷却速度可以很容易地调整小于每分钟0.5。慢慢凝结,发生在短和树枝水银上升。水的温度上升和下降的沸点/沸腾范围不小于0.1度不同。 It has been found that the depth of the layer of liquid sample at the time of the reading, the boiling point is about 3 mm in diameter. and that is the height of the vapour column to the top of the of less than 40 mm. Thus, the volume of it is around 13 times the volume of the liquid. The weight of the vapour, for a fraction of the weight of the fluid; for the water, and it is about one percent of the time. The current system is much easier to work with than the nearly comparable. During the charging of the tube, the sample is subjected to partial evaporation in these latter procedures. However, the current apparatus avoids the indefinite change in composition that this causes in liquid combinations.