Nitrometer

The main stem of the nitrometer widens into a bulb and then narrows to form a graduated tube. The usual graduation is of 8 ml. in o o2 ml. divisions. The graduations continue to the tap Tj at the top of the stem. Above Tj there is a small reservoir H to prevent splashing of the concentrated alkali when gas is expelled from the nitrometer and also to ensure that a small excess of potash is left as a liquid seal above the tap T ,. 

The combustion. The tap T2 is closed, T3 opened and the reservoir J raised (Fig. 87), to make sure that no air has been collected at the top of the nitrometer tube a small quantity of potash is left in H when tap T3 is closed and the reservoir J then lowered again. The carbon dioxide generator is switched off and tap T2 slowly turned on until it is fully opened. 

It sometimes happens that two or more bubbles coalesce to form one that hardly rises at all in the narrow part of the nitrometer tube this may be driven up to the rest of the collected gas at the top of the tube by gently squeezing the rubber pressure tubing connecting the movable reservoir J with the nitrometer proper. 

Ferrous Sulfdte Titration. For deterrnination of nitric acid in mixed acid or for nitrates that are free from interferences, ferrous sulfate titration, the nitrometer method, and Devarda s method give excellent results. The deterrnination of nitric acid and nitrates in mixed acid is based on the oxidation of ferrous sulfate [7720-78-7] by nitric acid and may be subject to interference by other materials that reduce nitric acid or oxidize ferrous sulfate. Small amounts of sodium chloride, potassium bromide, or potassium iodide may be tolerated without serious interference, as can nitrous acid up to 50% of the total amount of nitric acid present. Strong oxidizing agents, eg, chlorates, iodates, and bromates, interfere by oxidizing the standardized ferrous sulfate. 

Nitrometer Method. The nitrometer method also is used to determine nitric acid or nitrates in mixed acid or oleum. It involves the measurement of the volume of NO gas that is Hberated when mercury is oxidized by nitric acid. The method is based on the following reaction ... 

Salpeter-grube, /. saltpeter mine, -glitemesser, m. nitrometer, -hafen, m. niter pot. 

Salpeter-luft,/. nitrogen (old name), -messer, m. nitrometer, -milchsiure, /. lactic acid nitrate, -papier, n. niter paper, nitrous paper, -plantage, /. saltpeter plantation, -probe, /. saltpeter test, nitrate test saltpeter sample. 

Salpeter-schwefels ure, /. nitrosulfuric acid (a mixture) nitrosylsulfuric acid, -siederei, /. saltpeter works, -stkrkemehl, n. nitrated starch, -stoff, m. nitrogen, -strauch, m. niter bush Nitraria). -ung,/. nitrification, -verbindung, /. nitrate. -waC4)ge, /. nitrometer. 

Nitrometer. An app used for the estimation of nitrogen in Inorganic and organic nitrates by their reaction with Hg and sulfuric acid. For details of construction and operation see Vol 1, A373-L to A377-L... 

It was invented by lunge in 1890 under the name gasvolumeter (Ref 1). Ten years later, in the USA, it was modified and improved by F.I. duPont and described by Pitman as the duPont Nitrometer (Ref 2). At present, both macro and semi-micro nitrometers are in use, the latter being designed by Elving and Me Elroy (Ref 7)... 

Detn of N in NC by the Nitron method and comparison of results with those obtained by nitrometer] 5) W.C. Cope G.B. Taylor, The Determination of Nitrogen in Substances Used in Explosives , USBurMines, Tech Paper 160, Washington, DC (1917), 18-20... 

The NC samples were supplied from plant production lots and the listed nitrogen contents under Chemical Analysis were determined by a nitrometer technique these values are usually precise to within a few hundredths of 1%. The... 

Note The N detn was made by the Dumas method as modified byP. Jovinet and S. Courte-cuisse [MemServChimEtat 32, 16 (1945) and Etat Francais, FrP 510911 (1946)], because other methods, such as the nitrometer Or the Kjeldahl, did not give reliable results... 

The ease of N determination in PVN samples appears to be a function of the degree of polymerization. The nitrometer method gives consistent results, but are about 0.6% lower than the true values (Ref 6). Difficulty is experienced with high viscosity PVN. These products dissolve slowly in sulfuric acid, and give scattered results. Analytical methods based on titanous chloride,... 

Naphthalene, m.p. 81 , collects on the condenser in almost quantitative yield. If it is desired to follow the progress of the dehydrogenation, attach the side tube through a sofnolite (or soda lime) U-tube to a nitrometer filled with potassium hydroxide solution almost the theoretical quantity of hydrogen will be collected. 

Reingehalt (aus der Stickstoffbestimmung im Lunge-Nitrometer) nicht unter 98,5%... 

Reingehalt (Bestimmung mit Nitrometer Oder mit CrCI2) mindestens Typ 2 ... 

Nitrometer method, 27 191 Nitromethane production, 27 168 Nitronium perchlorate, 18 279 Nitronium tetrafluoroborate, 25 632 Nitroparaffins, 27 166-167... 

Kipp apparatus, electric combustion furnace,2 4 nitrometer, nickel dish, sieve of wire gauze, weighing bottle, and mixing tube are supplied by the laboratory. 

The Half-micro-nitrometer.—The half-micro-nitrometer used to collect the nitrogen has a capacity of 8-10 c.c., a volume which corresponds to 20-30 mg. of substance. A completely satisfactory degree of accuracy in measuring the gas is attained by graduating in sub-divisions of 0-02 c.c. 

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