Five-ball apparatus
The five-ball apparatus is a component of a device for the elemental analysis of organic substances, which was developed by the chemist Justus Liebig in 1831 . H. to determine which chemical elements (especially carbon , hydrogen , oxygen , nitrogen ) are present in this compound . The five-ball apparatus (originally called the Kali apparatus ) is used to collect and bind the carbon dioxide that is created when the sample to be examined is burned . For this purpose, the apparatus is filled with concentrated potassium hydroxide solution and the increase in mass due to the formation of potassium carbonate is determined by weighing (reaction equation: 2 KOH + CO 2 → K 2 CO 3 + H 2 O). The carbon content in the sample can be calculated from this. This is an important parameter when determining the molecular formula of an organic compound.
The apparatus was designed so compactly and easily that the weighing of the entire apparatus - with an analytical balance - could be carried out without processing the contained solution, which considerably shortened the duration of an elemental analysis.
A stylized Kali apparatus is used in the American Chemical Society logo .
At the Gießen Whitsun regatta, the winner of the women’s single A receives a challenge award in the form of a five-ball apparatus.
literature
- Justus Liebig: Instructions for the analysis of organic bodies . Vieweg, Braunschweig 1837 ( facsimile ).
- Justus Liebig: About a new apparatus for analyzing organic bodies, and the composition of some organic substances. , Annalen der Physik 21: 1-47, 1831.
Individual evidence
- ↑ Sarah Everts: A Most Important Artifact . In: Chemical & Engineering News . 93, No. 35, September 7, 2015, pp. 46–47.
- ↑ Awards / Badges of Honor. Retrieved June 9, 2019 .