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Excess acidity

Magnesium oxide is an effective nonsystemic antacid, ie, it is converted to the hydroxide. It does not neutralize gastric acid excessively nor does it hberate carbon dioxide. The light form is preferable to the heavy for adininistration in Hquids because it is suspended more readily. One gram of magnesium oxide neutralizes 87 mL of 0.1 NUCl in 10 min, and 305 mL in 2 h. [Pg.200]

Lead nitrate [10099-74-8] Pb(N02)2, mol wt 331.23, sp gr 4.53, forms cubic or monoclinic colorless crystals. Above 205°C, oxygen and nitrogen dioxide are driven off, and basic lead nitrates are formed. Above 470°C, lead nitrate is decomposed to lead monoxide and Pb O. Lead nitrate is highly soluble in water (56.5 g/100 mL at 20°C 127 g/100 mL at 100°C), soluble in alkalies and ammonia, and fairly soluble in alcohol (8.77 g/100 mL of 43% aqueous ethanol at 22°C). Lead nitrate is readily obtained by dissolving metallic lead, lead monoxide, or lead carbonate in dilute nitric acid. Excess acid prevents the formation of basic nitrates, and the desired lead nitrate can be crystallized by evaporation. [Pg.70]

Oil length, fatty acid, % Excess OH based on diacid equivalents, %... [Pg.36]

Part of Normal flow of decreased concentration of phosphoric acid Excess ammonia in reactor. Release to work area, with amount released related to quantitative reduction in supply. 1. Vendor delivers wrong material or concentration. 2. Error in charging phosphoric acid supply tank. Check phosphoric acid supply tank concentration after charging. [Pg.206]

The method may be applied to those anions (e.g. chloride, bromide, and iodide) which are completely precipitated by silver and are sparingly soluble in dilute nitric acid. Excess of standard silver nitrate solution is added to the solution containing free nitric acid, and the residual silver nitrate solution is titrated with standard thiocyanate solution. This is sometimes termed the residual process. Anions whose silver salts are slightly soluble in water, but which are soluble in nitric acid, such as phosphate, arsenate, chromate, sulphide, and oxalate, may be precipitated in neutral solution with an excess of standard silver nitrate solution. The precipitate is filtered off, thoroughly washed, dissolved in dilute nitric acid, and the silver titrated with thiocyanate solution. Alternatively, the residual silver nitrate in the filtrate from the precipitation may be determined with thiocyanate solution after acidification with dilute nitric acid. [Pg.353]

The easiest access to most benzyllithium, -sodium, or -potassium derivatives consists of the deprotonation of the corresponding carbon acids. Hydrocarbons, such as toluene, exhibit a remarkably low kinetic acidity. Excess toluene (without further solvent) is converted into benzyllithium by the action of butyllithium in the presence of complexing diamines such as A. Af.Af.jV -tetramethylethylenediamine (TMEDA) or l,4-diazabicyclo[2.2.2]octane (DABCO) at elevated temperatures1 a procedure is published in reference 2. [Pg.189]

Good results may sometimes be achieved with a 4 1 or 5 1 mole ratio of trichlorosilane to carboxylic acid. Excess trichlorosilane is desirable to compensate for losses of this volatile reactant over extended reflux periods. [Pg.85]

Kinetic studies of the hydride cluster [W3S4H3(dmpe)3] with acids in a non-coordinating solvent, i.e., dichloromethane, under the pseudo-first-order condition of acid excess, show a completely different mechanism with three kineti-cally distinguishable steps associated to the successive formal substitution of the coordinated hydrides by the anion of the acid, i.e., Ch in HCl [37]. The first two kinetic steps show a second-order dependence with the acid concentration. [Pg.113]

Cl3Si—i-C4H6.5D2.5 was employed as a solvent during the addition of Cl3SiH to 1-octene with chloroplatinic acid. Excess Cl3SiH was recovered free of Cl3SiD, and this indicates that the solvent in no way participated in the several equilibria. Similar experiments with Cl3Si—D and other olefins are summarized in Table III. [Pg.421]

Both FMOC and its hydrolysis products have similar absorption and fluorescence spectra to FMOC-amino acids. Excess FMOC remaining after derivatization reacts with water to form 9-fluorenylmethyl alcohol (FMOC-OH), and if this is not removed prior to sample injection, it elutes as a large, broad peak in the vicinity of proline. [Pg.54]

In a standard method [15, 19] soil organic matter is almost completely oxidized by boiling gently with a solution of potassium dichromate, sulphuric acid and phosphoric acid. Excess dichromate is determined by titration with standard ferrous sulphate solution. [Pg.318]

The function Data EqAH2, m simulates the pH-titration of a weak diprotic acid, AH2, in acid excess, with a strong base. The computation of the equilibria is similar to the examples Eql. m and Eq2. m given in the Chapters Example General 3-Component Titration (p.56) and Example pH Titration of Acetic Acid (p.58). From the present point of view, the important aspect is that all variables are collected in one structure s. The model is now stored in s.Model, the logP values in s. log beta, etc. Importantly, all the information contained in s is returned to the invoking programs. [Pg.170]

In most commercial processes, the compound is either derived from the sea water or from the natural brines, both of which are rich sources of magnesium chloride. In the sea water process, the water is treated with lime or calcined dolomite (dolime), CaO MgO or caustic soda to precipitate magnesium hydroxide. The latter is then neutralized with hydrochloric acid. Excess calcium is separated by treatment with sulfuric acid to yield insoluble calcium sulfate. When produced from underground brine, brine is first filtered to remove insoluble materials. The filtrate is then partially evaporated by solar radiation to enhance the concentration of MgCb. Sodium chloride and other salts in the brine concentrate are removed by fractional crystallization. [Pg.522]

Mercury(I) nitrate is prepared by action of metallic mercury with moderately dilute nitric acid. Excess mercury should be used to prevent the formation of mercury(II) nitrate. Hot or concentrated acid must be avoided as it yields the mercury(II) salt. [Pg.573]

Figure 2. NMR Spectra (60 MHz)15c of 3,3-dimethyl-2-butanol esters of four different nonracemic enantiomeric mixtures of carboxylic acids. Excess of the (R,R)- or (5,5 )-diasLereomers mandelate 22% atrolactate 18% MTPA 7.5% 0-methylmandelate 12.8%. Figure 2. NMR Spectra (60 MHz)15c of 3,3-dimethyl-2-butanol esters of four different nonracemic enantiomeric mixtures of carboxylic acids. Excess of the (R,R)- or (5,5 )-diasLereomers mandelate 22% atrolactate 18% MTPA 7.5% 0-methylmandelate 12.8%.
Vanadium lends itself also to iodometric method of determination. The vanadate solution is reduced with hydrobromic acid, excess of potassium iodide is added, and the iodine thereupon liberated is estimated with sodium thiosulpliate solution. The reaction is 3... [Pg.113]

Prepared by reaction (I) of iodine and mercuric oxide (see also Mercury) suspension in water, mercuric iodide being simultaneously formed. (2) of sodium hypoiodite and an acid, excess acid yielding iodine. [Pg.816]

Important chemical characteristics of the soil include the total exchange capacity for cations, expressed as total meq of cations per 100 gm of soil, and the base status, which is the percentage saturation of the negative charge with cations such as calcium, magnesium and sodium. The more productive soils are about 80% saturated with calcium and magnesium. Excessive hydrogen and aluminum saturation (much over 15%) is termed soil acidity. Excess sodium saturation (12% or more) leads to dispersiveness of the soil and poor productivity. [Pg.1499]

The free base may be isolated by dissolving the sulphate in water slightly acidified with dilute sulphuric acid. Excess of sodium carbonate solution is then added, when the quinine is precipitated. It is filtered off, washed and dried. M.P. 175°. [Pg.401]

The alkaline liquid is decanted into another flask, diluted with an equal amount of water and boiled until it ceases to smell of ammonia it is then allowed to cool somewhat, and sufficient hydrochloric acid added drop by drop to render the liquid distinctly acid, excess being avoided. A thread of defatted wool, 10-15 cm. long, is then placed in the liquid and the latter boiled for about 5 minutes. [Pg.201]


See other pages where Excess acidity is mentioned: [Pg.380]    [Pg.474]    [Pg.548]    [Pg.256]    [Pg.114]    [Pg.114]    [Pg.336]    [Pg.63]    [Pg.39]    [Pg.380]    [Pg.54]    [Pg.99]    [Pg.327]    [Pg.187]    [Pg.266]    [Pg.262]    [Pg.121]    [Pg.306]    [Pg.268]    [Pg.247]    [Pg.193]    [Pg.315]    [Pg.432]    [Pg.380]    [Pg.146]    [Pg.815]    [Pg.665]   
See also in sourсe #XX -- [ Pg.451 ]

See also in sourсe #XX -- [ Pg.451 ]




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Acid Excess

Adsorbed water excess acidity

Amino acid excess

Amino acids enantiomeric excesses

Ascorbic Acid in excess

Blends acid-excess

Excess acidity equation

Excess acidity method

Excess stomach acid

Peptic ulceration excessive acid secretion

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