Ammonium acetate solution, strong

Weak acids with weak bases. The titration of a weak acid and a weak base can be readily carried out, and frequently it is preferable to employ this procedure rather than use a strong base. Curve (c) in Fig. 13.2 is the titration curve of 0.003 M acetic acid with 0.0973 M aqueous ammonia solution. The neutralisation curve up to the equivalence point is similar to that obtained with sodium hydroxide solution, since both sodium and ammonium acetates are strong electrolytes after the equivalence point an excess of aqueous ammonia solution has little effect upon the conductance, as its dissociation is depressed by the ammonium salt present in the solution. The advantages over the use of strong alkali are that the end point is easier to detect, and in dilute solution the influence of carbon dioxide may be neglected. 

Pharmaeosiderite may be obtained artificially 5 by heating ferric orthoarsenate and water in a sealed tube at 200° C. or by boiling the ferric salt with ammonium acetate solution acidified with acetic add. The product contains considerably more water than the natural mineral, but loses it when strongly heated. The mineral loses 5 molecules of water up to 233 1° C., when decomposition begins, the products being ferric and arsenic oxides.8... 

The buffer capacity is purely and simply the sum of the buffer components mixture. This property is true regardless of the couple s number and the electrical charge of the acidic form. In order to illustrate this point, let s consider a 0.1 mol/L ammonium acetate solution [pKg (acetic acid) = 4.75) and (pK (ammonium ion) = 9.24]. The preceding relation permits us to calculate P as a function of the pH value (Fig. 6.4). The latter is adjusted by adding a strong acid or a strong base. 

Add a few drops of acetic acid and a little ammonium or potassium acetate solution to a moderately strong solution of tartaric acid or a neutral tartrate. On stirring with a glass rod, the acid potassium or ammonium tartrate will be precipitated. 

The MS and MS/MS behaviors of the four corticosteroids under positive ion ESI was investigated using direct infusion of standard solutions into the mass spectrometer. In preliminary experiments, it was observed that all four corticosteroids formed strong [M+Na]+and [M+K]+ ions along with relatively weaker [M+H]+ ions in methanol/acetonitrile/water. However, an acidic 2 mM ammonium acetate buffer... 

A wide-mouthed 250-cc. flask (Note 1) containing a mixture of 50 g. (0.25 mole) of technical 2,4-dinitrochlorobenzene (Note 2) and 18 g. (0.23 mole) of ammonium acetate is half immersed in an oil bath. The flask is fitted with a reflux condenser and an inlet tube, the lower end of which is at least 2 cm. wide (to prevent clogging), and nearly touches the surface of the reaction mixture. During the operation ammonia gas is introduced through a bubble counter which contains a small amount of strong potassium hydroxide solution (12 g. of potassium hydroxide in 10 cc. of water). 

Silver may be separated from Ce, Zr, Th, Be, and Fe(III), on strongly acidic cation-exchangers, by converting these metals into anionic complexes, or separated from Cu, U, Al, and Zn by selective elution with nitric acid [14]. After retention of Pb, Ag, and Hg on Dowex 50, lead is eluted first with 0.25 M ammonium acetate, then silver with 0.5 M ammonia solution. Silver has been separated on a cation-exchanger from Hg, Co, Ni, and Zn on the basis of the differing stabilities of their EDTA complexes at pH 4.6 [15]. Silver retained in a column with a macroporous cation-exchange resin bed has been eluted with 2 M HNO3 or 0.5 M HBr in aqueous acetone solution [16]. 

Methyl Cyanide, CH3CN, may be considered as a representative of the class. It is a liquid of strong but not unpleasant odor, which boils at 81°. It is formed by boiling a solution of methyl iodide and potassium cyanide in alcohol diluted with water. The reaction takes place slowly. It is best prepared by distilling ammonium acetate, or, better, acetamide, with phosphorus pentoxide —... 

Both commonly used elution methods with ammonium acetate/ACN and water/ACN with TFA were suitable for determination of MC, but performance of these methods was strongly dependent on the analytical column used. Addition of water to methanolic standard solutions of MC significantly increased the sensitivity of UV detection and resulted in better chromatography. 

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