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Hydrazine analytical reactions

Hydrazine hydrate is used as a reducing agent in synthetic and analytical reactions and as a solvent for many inorganic compounds. It also is used with methanol as a propellant for rocket engines. Another apphcation is catalytic decomposition of hydrogen peroxide. [Pg.349]

Figure 9 Reaction scheme for NPH with carboxylic acid and hydrazine analytical reagents. Figure 9 Reaction scheme for NPH with carboxylic acid and hydrazine analytical reagents.
Hydrazine reduces potassium iodate in hydrochloric acid forming iodine monochloride, a reaction of analytical importance ... [Pg.345]

Other molecules capable of serving as coreactants in this reaction type are aliphatic amines [26], amino acids [27-30], NAD(P)H [31], hydroxide ions [32], hydrazine [32], and NaBITt [32], although each reaction is different and there are variations in the mechanism of each analyte interacting with [(bpy)3Ru]2+. [Pg.162]

Calculations of volumetric analysis ordinarily consist of transforming the quantity of titrant used (in chemical units) to a chemically equivalent quantity of analyte (also in chemical units) through use of a stoichiometric factor. Use chemical formulas (NO CALCULATIONS REQUIRED) to express this ratio for calculation of the percentage of (a) hydrazine in rocket fuel by titration with standard iodine. Reaction ... [Pg.363]

A stirred slurry of 2.93 g 0-(5-benzyloxy-3-indolyl)-Qf-sulfhydrylacrylic acid (9 mmol) in 10 mL absolute ethanol was treated with 2.4 mL 99-100% hydrazine hydrate (0.048 mol), and the mixture was heated under nitrogen. Reaction occurred at 60" C, accompanied by vigorous evolution of H2S. After the mixture was refluxed for 2 h, the liberation of H2S had ceased (no black precipitate when a stream of nitrogen was passed through the reaction solution and exited into aqueous lead acetate), and the flask was allowed to cool to room temperature. The crystalline product, the hydrazine salt of j0-(5-benzyloxy-3-indolyl)pyruvic acid hydrazone, was filtered, washed with cold ethanol (3x8 mL), and then dried. It weighed 2.35 g and was found to be analytically pure. [Pg.1262]

The cell concentration was determined by optical density (OD) measurement at 600 nm and compared with an OD versus dry weight calibration curve. Nitrate and nitrite concentrations were measured using a segmented flow analyzer (Skalar analytic ). Nitrite detection was based on the colorimetric reaction with N-(l-naphthyl)-ethylenediamine nitrate was detected as nitrite by the same method after reduction by hydrazine. DOC was also measured using the segmented flow analyzer. Carbon compounds were detected as... [Pg.1081]

The optimum conditions for the reaction of acetone and hydrazine< > have not been studied thoroughly enough for this reaction to be at present recommended for an analytical method. [Pg.127]

On the other hand, the kinetic reduction waves of aldopentose hydrazones, obtained by adding the pentose to 0-053 M dibasic sodium phosphate containing 0-1 M hydrazine sulphate (final pH 2-3), can be used for analytical purposes.The governing chemical reaction, and hence the limiting current too, are pH dependent, and it is therefore necessary to control the pH carefully. Owing to differences in equilibrium and/or, rate constants, the limiting currents at pH 2-3 vary substantially for different pentoses. This can be utilized for the analysis of certain sugar mixtures. [Pg.127]

An interesting area of luminol ECL is the study of electrogenerated catalysts that promote both the conventional CL reaction and the luminol/H202 ECL reaction. This allows the detection of analytes directly or by the enhancement of luminol ECL for the detection of analytes. A recent example is the enhancing effect of hydrazine on luminol ECL based on hydrazine s in situ electrochemical modi-... [Pg.476]

A new synthesis of monoalkyl hydrazines has been reported which overcomes many problems associated with previous methodology. In a modified procedure analytically pure monoalkylhydrazine hydrochlorides are available from aldehydes or ketones by reaction with t-butyl carbazate. The use of the t-butyl group greatly facilitates hydrolysis of the intermediate carbazate, giving direct in situ formation of the hydrazine hydrochloride salts (Scheme 39). [Pg.210]

Kinetic and mechanistic studies of yet more complicated species will be noted more briefly. Polarographic reduction of tungstomolybdosilicates (SMo + W=12 Si= 1) starts with a dissociative step. A rate law and initial rates have been reported for the formation of phosphovanadomolybdate (Mo= 10 V=2 P= 1) from dinuclear molybdenum and dinuclear vanadium oxoanions. Further kinetic information on these analytically important phosphomolybdovanadate species is available, in relation to their reactions with hydrazine. Kinetics of exchange are reported between [UfPWnOss).,] - or [UCPaWi OeOa] - and [WO4] -, and of W between [SiWi Nb204ol - and [HsWeOai] -. ... [Pg.171]


See other pages where Hydrazine analytical reactions is mentioned: [Pg.320]    [Pg.290]    [Pg.368]    [Pg.146]    [Pg.275]    [Pg.57]    [Pg.155]    [Pg.551]    [Pg.154]    [Pg.295]    [Pg.319]    [Pg.146]    [Pg.3043]    [Pg.65]    [Pg.86]    [Pg.371]    [Pg.683]    [Pg.47]    [Pg.3042]    [Pg.735]    [Pg.152]    [Pg.226]    [Pg.86]    [Pg.181]    [Pg.267]    [Pg.287]    [Pg.1536]    [Pg.3842]    [Pg.3843]    [Pg.310]    [Pg.312]    [Pg.902]    [Pg.323]    [Pg.664]    [Pg.31]    [Pg.367]    [Pg.209]    [Pg.443]    [Pg.258]   
See also in sourсe #XX -- [ Pg.320 ]




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