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A boiling tube is a large test tube intended specifically for boiling liquids. A test tube filled with water and upturned into a water-filled beaker is often used to capture gases, e.g. in electrolysis demonstrations. A test tube with a stopper is often used for temporary storage of chemical or biological samples.
In addition, heating test tubes should never be pointed towards any person, just in case bumping does occur. Whenever a liquid is cooled below its boiling point and re-heated to a boil, a new boiling chip will be needed, as the pores in the old boiling chip tend to fill with solvent, rendering it ineffective. [2]
These tubes are usually made of glass, but can also be made of plastic or metal. They vary in size and purpose. Laboratory sample tubes must not be confused with glass tubing, which can be utilized to carry fluid between laboratory equipment. Example laboratory sample tubes are listed below: Ignition tube; Test tube; Boiling tube; NMR tube
The Thiele tube, named after the German chemist Johannes Thiele, is a laboratory glassware designed to contain and heat an oil bath. Such a setup is commonly used in the determination of the melting point or boiling point of a substance. The apparatus resembles a glass test tube with an attached handle.
The two outer tubes (#3 and #4) form an insulating dead air chamber (shaded). Vapor rises from a boiling flask into space (1), proceeds up through the space between tubes #2 and #3, then down the space between tubes #1 and #2, and finally up between tube #1 and the central rod.
The atmospheric pressure boiling point of a liquid (also known as the normal boiling point) is the temperature at which the vapor pressure equals the ambient atmospheric pressure. With any incremental increase in that temperature, the vapor pressure becomes sufficient to overcome atmospheric pressure and cause the liquid to form vapor bubbles.
A Thiele tube is an alternative heating vessel. The Siwoloboff method is used to determine the boiling point of small samples of liquid chemicals. A sample in an ignition tube (also called a fusion tube) is attached to a thermometer with a rubber band, and immersed in a Thiele tube, water bath, or other suitable medium for heating. A sealed ...
Special electrically powered heating mantles are available in various sizes into which the bottoms of round-bottom flasks can fit so that the contents of a flask can be heated for distillation, chemical reactions, boiling, etc. Heating can also be accomplished by submerging the bottom of the flask into a heat bath, water bath, or sand bath.