GB/T616-2006 Boiling Point Determination Device Glass Instrument

Method principle: As the temperature of the liquid increases, its vapor pressure also increases. When the vapor pressure of the liquid is equal to atmospheric pressure, boiling begins. The boiling temperature of a liquid under standard conditions (1 013,. 25 hPa, 0 ℃) is the boiling point of the liquid.

A three necked round bottom flask, a test tube, and a measuring thermometer are connected by a rubber stopper. The lower end of the measuring thermometer is 20mm away from the liquid level of the test tube. An auxiliary thermometer is attached to the measuring thermometer so that its mercury ball is in the middle of the mercury column outside the rubber stopper of the measuring thermometer. About half of its body of silicone oil is injected into the flask.

1.1 Three necked round bottom flask

The effective volume of a three necked round bottom flask is 500ml

1.3 Test tube

The test tube is 190mm-200mm long and has a side hole with a diameter of 2MM about 15mm from the mouth of the test tube.

1.3 Rubber stopper

The outer side of the rubber plug has an air outlet groove.

1.4 Measuring thermometer and auxiliary thermometer

The measuring thermometer should comply with the provisions of JJG130, and a fully immersed mercury thermometer with a division value of 0.1 ℃ should be selected. The market value range is suitable for the boiling point temperature of the sample. An auxiliary thermometer should be used to calibrate the mercury column exposed outside the plug of the measuring thermometer during the distillation process.

The temperature range of the auxiliary thermometer is 0 ℃ -50 ℃, with a division value of 1 ℃

determination

Measure an appropriate amount of sample and inject it into a test tube, with the liquid level lower than the liquid level of silicone oil in the flask. Heating, when the temperature rises to a certain value and remains constant for a considerable period of time, this temperature is the boiling point of the sample to be tested. Simultaneously record the room and air pressure.