Sodium hydrogenocarbonate

The kinetics of P-elimination were followed by the increase of the absorbance at 235 nm (Albersheim et al., 1960). The pH of the pectin solution (1 ml, already in the spectrometer) was adjusted at t = 0 by adding 1 ml of 0.2 M sodium hydrogenocarbonate sodium carbonate buffer. This buffer did not have a prohibitively high absorbance at 235 nm. 

The monomer silane diol (5) was prepared by hydrolysis of the bis-chlorosilane (4) in the presence of sodium hydrogenocarbonate NaHCO at reflux of diethyl ether for 24 h. The hydrolysis was quantitative. The silane diol (5) was characterized by IR, where a narrow band at 3690 cm and a wide band between 3650 and 3050 cm were observed, respectively, for free t)=siOHand bonded t)= aoH Us H- and F-NMR spectra exhibited the expected signals and its Si-NMR spectrum showed a singlet at -i-16.4ppm characteristic for a 5 = siOH and no trace of the starting chlorosilane at -i-31 ppm. ... 

L. C. Clark first suggested in 1956 that the test solution be separated from an amperometric oxygen sensor by a hydrophobic porous membrane, permeable only for gases (for a review of the Clark electrode see [88]). The first potentiometric sensor of this type was the Severinghaus CO2 electrode [150], with a glass electrode placed in a dilute solution of sodium hydrogenocarbonate as the internal sensor (see fig. 4.10). As an equilibrium pressure of CO2, corresponding to the CO2 concentration in the test solution, is established in the... 

A solution of the dry D-glucose diethyl dithioacetal (10.725 g 37.5 mmol) 2-methoxypropene (3.245 g 45 mmol) in anhydrous DMF (130 mL) and p-toluenesulfomc acid (375 mg) was kept for 68 h at 0°C. The homogeneous mixture was kept with exclusion moisture until TLC indicated that all the starting material had reacted, and it was then poured into a solution of sodium hydrogenocarbonate (2% w/v, 60 mL). This mixture was extracted with ether (4 x 30 mL). The combined ether extracts woe washed with water (2 x 30 mL), dried (magnesium sulfate), and evaporated, giving yellowish crystals (8.275 g, 68%) that were recrystallized twice from dichlorometbane petroleum ether to give colorless crystals of 14 yield 5.735 g (47%), mp 73J-74.5°C, [a]D-ll° (c 2.027, methanol). 

In the case of the oxidation by KMn04, the reactions are usually performed in a hot medium, either in a basic system (KOH) by monitoring the pH or in buffer medium (sodium hydrogenocarbonate [20]). It has been shown that when such a reaction is carried out in an acid medium the yield decreases drastically [21]. 

The reactivity of solid sodium with pure oxygen depends on traces of impurities in the metal. In ordinary air, sodium metal forms a sodium hydroxide film (NaOH), which rapidly exothermically absorbs traces of carbon dioxide and moisture always present in air, forming sodium hydrogenocarbonate, or simply bicarbonate (NaHCOj). Sodium is more reactive in air as a liquid than as a solid, and the liquid can ignite spontaneously at about 125°C. When burning in dry air, sodium burns quietly, giving off a dense, white-aerosol, strongly caustic smoke of... 

Obtainedbyreactionofl-propanolwith3-(chloromethyl)-4-hydroxypropiophenone in the presence of sodium hydrogenocarbonate [6982]. 

Sodium is the alkali metal of most commercial importance by far, and the principal sodium compounds of industrial and commercial importance are the chloride (NaCl), the anhydrous carbonate (i.e., soda ash, Na COj), hydrogenocarbonate (i.e., baking soda, NaHCOj), the hydroxide (i.e., caustic soda, NaOH), and the sulfate (Na SO. lOH O, Glauber salt). Large amounts of sodium chloride are, for instance, used in the production of bulk quantities of other industrial chemicals. To a lesser extent sodium cyanide, sodium peroxide, sodium sulfide, sodium borates, sodium phosphates, and sodium alkyl sulfates are also industrially produced. Nevertheless, the aim of this book is not to detail the uses of sodium compounds, which are extensively described in comprehensive industrial inorganic chemistry textbooks thus only the uses and applications of metallic sodium are listed in Table 4.15. 

Citric acid naturally exists in large amounts in a variety of fruits and vegetables (notably citrus fruits). Additive in formulation for elfervescent reaction (production of CO2) with sodium bicarbonate (hydrogenocarbonate). 

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