Sodium acetate buffer solution

The pH of the acetic acid-sodium acetate buffer solution is given by the equation ... 

Thus the pH of the acetic acid-sodium acetate buffer solution is only altered by 0.09 pH unit on the addition of the hydrochloric acid. The same volume of hydrochloric acid added to 1 litre of water (pH = 7) would lead to a solution with pH = -log(O.Ol) = 2 a change of 5pH units. This example serves to illustrate the regulation of pH exercised by buffer solutions. 

In summary, sodium acetate buffer solutions at pH 5.5 and at the soil to solution ratio of 1 25 only extract the carbonate from calcareous soils with 10-20% of carbonate, and, at pH 5.0, all of the carbonate from soils with 30-50% of carbonate is dissolved. A second extraction with a fresh buffer solution is required for soils with more than 50% carbonate. The dissolution kinetics of carbonate showed that six hours of extraction are generally sufficient for complete carbonate dissolution. The part of the carbonate fraction not dissolved at the carbonate fraction step is mainly... 

If 1 ml of 1 M HCl is added to this sodium acetate buffer solution, the pH change may be calculated as follows. Again, we require the Henderson-Hasselbalch equation ... 

Another transient aminoxyl radical has been generated , and employed in H-abstraction reactivity determinations" . Precursor 1-hydroxybenzotriazole (HBT, Table 2) has been oxidized by cyclic voltammetry (CV) to the corresponding >N—O species, dubbed BTNO (Scheme 9). A redox potential comparable to that of the HPI —PINO oxidation, i.e. E° 1.08 V/NHE, has been obtained in 0.01 M sodium acetate buffered solution at pH 4.7, containing 4% MeCN". Oxidation of HBT by either Pb(OAc)4 in AcOH, or cerium(IV) ammonium nitrate (CAN E° 1.35 V/NHE) in MeCN, has been monitored by spectrophotometry , providing a broad UV-Vis absorption band with A-max at 474 nm and e = 1840 M cm. As in the case of PINO from HPI, the absorption spectrum of aminoxyl radical BTNO is not stable, but decays faster (half-life of 110 s at [HBT] = 0.5 mM) than that of PINO . An EPR spectrum consistent with the structure of BTNO was obtained from equimolar amounts of CAN and HBT in MeCN solution . Finally, laser flash photolysis (LFP) of an Ar-saturated MeCN solution of dicumyl peroxide and HBT at 355 nm gave rise to a species whose absorption spectrum, recorded 1.4 ms after the laser pulse, had the same absorption maximum (ca 474 nm) of the spectrum recorded by conventional spectrophotometry (Scheme 9)59- 54... 

At an AI/O4 mol ratio of approximately 0.4, Al preferentially replaces tetrahedral Fe (A-site). Ardizzone et al. (1983) reported that magnetite prepared in sodium acetate buffer solution contains up to 2.3 mg g Na in the structure. 

Add the strong acid HC1 to an acetic acid—sodium acetate buffer solution, however, and the H ions produced by the HC1 do not stay in solution to lower the pH because they react with the acetate ions, C2H302-, of sodium acetate to form acetic acid, as shown in Figure 10.19. (Remember that acetic acid, being a weak acid, stays mostly in its molecular form, HC2H302, and so does not contribute hydronium ions to the solution.) Add the strong base NaOH to the acetic acid—sodium acetate buffer solution, and the OH-ions produced by the NaOH do not stay in solution to raise the pH because they combine with H+ ions from the acetic acid to form water, as shown in Figure 10.20. 

Now suppose that we add 0.01 mol of HC1 to 1.00 L of the 0.10 M acetic acid-0.10 M sodium acetate buffer solution. The added strong acid will convert 0.01 mol of acetate ions to 0.01 mol of acetic acid because of the neutralization reaction... 

Pour 300 mL 0.1M Sodium acetate buffer solution (pH 4.7) into the vessel and start the stirrer and add 2.5 g of cellulase. (Typical FPU of commercially prepared enzyme is about 100 FPU/g.)... 

Preparation of Wood-Methyl Methacrylate Graft Copolymer. Wood Meal (0.5 g), an acetic acid-sodium acetate buffer solution with pH 4.6 (5 ml), a ferrous sulfate aqueous solution (5 ml FeSO 1x10 mole), MMA (8 ml), and a hydrogene peroxide aqueous solution ( 5 ml HO. 1x10 mole) were mixed in this order. After degassed, the flask was sealed and shaken at 50 °C for 1 to 8 h. The reaction mixture was poured into a large excess of methanol. To remove homo polymer, the product was then extracted with acetone for 36 - 72 h. 

Polystyrene-Wocfc-poly(isocyanodipeptide)s PS40- -PIAA10 (AA = L-alanine-L-alanine-COCTNa+) (Fig. 4a), introduced by Nolte et al. [26], were found to form bilayered vesicles in aqueous sodium acetate buffer solution at pH 5.6. The vesicles observed had diameters ranging from tens to hundreds of nanometers and a bilayer... 

Buffered Solutions. Single phase experiments in 0.5 M acetic acid-0.5 M sodium acetate buffer solutions, with HS07 (0.01 to 0.04 H) in large excess over oxygen, gave approximately a zero order dependence on oxygen. The data actually indicated a somewhat less than zero order initially which gradually became zero order as the reaction approached completion. The complete rate law for these buffered solutions at pH 4.7 appears to be... 

Bls-(azo-2,4-dihydroxy)-biphenyl was prepared by adding bisdiazotized benzidine to resorcinol (100% excess) in a sodium acetate buffered solution. The mixture finally was made alkaline with sodium hydroxide. The product was purified by washing. 

Reagents used in the test, including sodium hydroxide, hydrochloric acid, sulfuric acid and cobalt sulfate were analytical grade without farther purification. PC88A extractant was industrial-grade products with a purity of 93%. Acetic acid-sodium acetate buffer solution was prepared on our laboratory. The resin used in the test was the HPD-100 Styrene-divinyl benzene porous adsorbing resins. The cobalt raw materials used in the test are listed in Table 1. 

The test procedure gives information about possible changes in the glass surface (stain formation) under the influence of lightly acidic water (for example perspiration and acidic condensates) without vaporization. Two test solutions are used. Test solution I is a standard acetate solution with pH = 4.6, for classes FR 0 to 3. Test solution It is a sodium acetate buffer solution with pH = 5.6, for classes FR 4 and FR 5. 

Sodium acetate buffer solution 3 g of 96% CH3COOH Suprapur, 4.1 g of CHsCOONa Suprapur, 497 mL of ultrapure water. 

Sodium acetate buffer solution - mix 100 ml of N sodium acetate with 15 ml of N acetic acid. 

Transfer 5 ml of the test solution to a 50 ml beaker. Add 1 ml of N hydrochloric acid and then 0.5 ml of sodium acetate buffer solution and 1 drop of fluorescein solution. Mix thoroughly and then add 1 drop of chloramine T solution. Mix by swirling and set aside for 30 seconds, then stop the reaction by adding 2 drops of alkaline thiosulfate reducing agent. Treat the blank solution in a similar manner. When bromine is present in the sample, a rose-pink colour will be developed in the test solution compared with the yellow-green blank solution. (Note Iodine also gives a positive result with this test.)... 

Add the required volume of distilled water to take the volume of each solution up to 35 cm Add 5 cm of Tiron reagent and neutralize to Congo red paper with 50% ammonia solution, add 5 cm of pH 4.7 acetic acid/sodium acetate buffer solution and dilute to the mark with distilled water. 

Weigh 2 mg into a 50-ml graduated flask and dissolve in sodium acetate buffer solution, pH 4 5 (prepared by mixing 600 ml of 0-2M acetic acid with 400 ml of 0-2M sodium acetate). Dilute to volume with the buffer solution and mix. 

McBride and Evans [10] developed a rapid voltametric method for the estimation of antioxidants and tocopherols in oils and fats. The sample solutions were prepared by dissolving the oil or lard sample in an appropriate solvent, e.g., in most cases 0.12 M sulfuric acid in ethanol - benzene (2 1). The solutions were analysed with use of a linearly varying potential and a stationary, planar vitreous-carbon electrode, with a standard calomel electrode and a platinum-wire counter-electrode. Separate peaks were obtained for a-, y- and 8-tocopherol the peak for the P-isomer, was superimposed on that for the y-tocopherol. BHA (>10 ppm) can be determined in vegetable oil under the same conditions, provided that 8-tocopherol is absent. Kohler and co-workers [11] described a polarographic method for the determination of 4-4 thiobis(BHT) in food. The antioxidant was first nitrated, preferably with fuming nitric acid - concentrated sulfuric acid (1 1) at 20 °C for 1 hour. The polarography was carried out on the resulting solution after dilution and addition of urea and sodium acetate buffer solution. The Ey for the nitrated compound was -0.54 V versus the... 

---