A gasometer is a laboratory instrument for collecting and storing gases , as well as an approximate estimate of their volumes [3] [4] . It is a vessel made of thick glass , copper or tin (usually portable, often graduated) with a capacity of up to several tens of liters and is designed for storing and delivering gas under pressure slightly exceeding atmospheric pressure .
In liquid (wet) gas meters, the collection of gas is based on the displacement of the barrier liquid into the pressure funnel by the collected gas, and the extraction of gas is based on the displacement of gas by the liquid from the funnel (see the drawing with the image of Berzelius glass gasometer ) [5] . Water , saline or mercury is used as a barrier fluid. The gas to be stored must not interact with the barrier liquid and be insoluble in it. The lack of liquid gas meters - the possibility of impurities from the barrier fluid in the stored gas [6] . In addition, as the gas is withdrawn, the pressure in the Berzelius gas meter gradually decreases. If constant gas pressure is required, a Betty gas meter is used [5] .
Before starting work, the Berzelius laboratory gasometer, a thick-walled glass bottle with a funnel on thin section, is completely filled with water, pouring it through the funnel with both cranes open; the last air bubbles are removed, slightly raising and lowering the funnel. Then the valve on the gas outlet tube is closed, the plug is removed from the drain pipe and the gas meter is connected to the gas source via the gas pipe through the same pipe. The gas gradually fills the vessel, displacing the water through the drain pipe into the pan or sink; the volume of gas is determined by the divisions applied to the body of the gas meter. To get the gas flow from the gasometer, the pressure funnel is filled with water, put a plug on the drain pipe and open both taps. Water displaces the gas that escapes through the flue pipe [5] .
Refueling the gas meter is not allowed in order to avoid accidental mixing of the remnants of the old gas with the new, for example, hydrogen with oxygen . Before each refilling, make sure that the gas meter is completely filled with water. It is not recommended to fill gas meters with flammable gases (hydrogen, methane , acetylene , etc.) capable of forming explosive mixtures with air [7] .
An ordinary metal gasometer is constructed on the same principle as the above described Berzelius gasometer. Metallic gas meters supply a side water tube calibrated in units of measurement of gas volume: the water level in the transparent tube indicates the amount of gas in the gas meter [3] .
For work with gases that dissolve in water or with dry gases that must not contain water vapor, use a Bunsen mercury gas meter [4] or dry gas meters [8] .
See also
- Gas analysis
- Gasholder
- Laboratory equipment
Notes
- ↑ Mendeleev D., Fundamentals of Chemistry, 1903 , p. 40
- ↑ Mendeleev D., Fundamentals of Chemistry, Part 1, 1949 , p. 137.
- ↑ 1 2 TSB, 2nd ed., Vol. 10, 1952 , p. 66
- ↑ 1 2 BME, vol. 6, 1929 , p. 85 (stb. 169).
- ↑ 1 2 3 B. D. Stepin, Technique of laboratory experiment in chemistry, 1999 , p. 496-497.
- ↑ Rapoport, F. M., Ilinsky, A. A., Laboratory Methods for the Production of Clean Gases, 1963 , p. 17
- ↑ Stepanova N.A. Preparative Chemistry, 2009 , p. 48.
- ↑ Borovaya MS, Laboratory Assistant, Oil and Gas Laboratory, 1968 , p. 238.
Literature
- Big Medical Encyclopedia / Ch. ed. N.A. Semashko . - M .: Soviet Encyclopedia , 1929. - T. 6: Dislocation - Giemsa. - 432 s.
- Great Soviet Encyclopedia / Ch. ed. B. A. Vvedensky. - 2nd ed. - M .: Big Soviet Encyclopedia , 1952. - T. 10: Gazelle - Germanium. - 620 s.
- Borovaya M.S. Laboratory Assistant, Oil and Gas Laboratory. - M .: Nedra, 1968. - 309 p.
- Mendeleev D. Fundamentals of Chemistry. - 7. - SPb. : Tipo-lithography M. P. Frolova, 1903. - XVI + 800 p.
- Mendeleev D. Compositions. Volume XIII. Basics of Chemistry. Part I. - Moscow : Publishing House of the Academy of Sciences of the USSR, 1949. - 851 p.
- Rapoport, F. M., Ilinskaya, A. A. Laboratory methods for obtaining pure gases. - M .: Goskhimizdat, 1963. - 420 p.
- Stepanova N. A. Preparative Chemistry . - Vitebsk: VSU them. PM Masherova, 2009. - 193 p.
- Stepin B. D. Technique of laboratory experiment in chemistry . - M .: Chemistry, 1999. - 600 p. - ISBN 5-7245-0955-5 .