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Electrometric measurement

Quantitative measurements of the strength of an acid are best based on electrometric measurements of the pH of the partly neutralized solution. Conductivity measurements are likely to give ionization constants that are too high due to the presence of conducting impurities. Estimates of acid strength from rate data are also somewhat unreliable... [Pg.179]

Precipitation titrations with AgNC>3 can be carried out using electrometric measurement of [Ag+] (to be discussed... [Pg.325]

The use of pure DMSO for pKa measurement has obvious advantages because of its unique properties.3 Thus its high p/Ca enables determination of acidities of very weak acids, and its large dielectric constant facilitates electrometric measurement. Nevertheless, a practical disadvantage of this system lies in the rigours associated with techniques using pure DMSO. These practical difficulties are considerably ameliorated in methods employing aqueous or alcoholic DMSO. Two such methods are available, as described below.4... [Pg.147]

With a simple underway technique for measuring pH, a strong correlation previously was found between pH, coastal upwelling, and the resulting planktonic production 6-8). However, discussions of these measurements were limited to changes that were greater than 0.1 pH units because, previously, pH was measured electrometrically and the electrometric measurement of pH may involve an absolute error of 0.1 pH units (9) thus, no attempt was made to look at the finer structure. [Pg.393]

Kinetics of the reaction of diazoacetic ester with acids have been studied intermittently over a period of fifty years. The earliest work indicated that the reaction was first order in ester and subject to specific acid catalysis (see Bell, 1941a). Kinetics were measured by the rate of nitrogen evolution, and at a time when electrometric measurements of pH were not available, rate constants for the reaction were used to... [Pg.336]

Recently, a number of municipalities have become so concerned with the problem that they have installed automatic ozone recorders at strategic locations. Some of these instruments are based on the chemical determination of ozone by oxidation of potassium iodide, and colorimetric or electrometric measurement of the extent of the reaction. Others are spectrophotometric instruments a few are based on rubber cracking. The value of the chemical determinations of ozone in the presence of the oxidizing or reducing substances present in polluted atmospheres is questionable. Spectrophotometric methods require a light path of a few hundred feet and cannot be moved easily from one location to another. Determination by rubber cracking is... [Pg.87]

Electronic methods include the use of well-calibrated commercial thermo-couple- or thermistor -based instruments. These are typically built into meters used for other types of electrometric measurements, for example, pH and dissolved oxygen. [Pg.252]

Again, we have not included activity corrections, because (both didactically and computationally) these are best added afterwards whenever such corrections are required. The principles involved are the same as those explained in section 4.10 activity corrections apply to the equilibrium constants (such as Kfl, Ksl, and k) but not to the mass and charge balance relations and their derivatives, such as a ligand balance or an electron balance. Furthermore, electrometric measurements must be corrected for activity effects, but spectroscopic measurements should not be. At any rate, as the example of HgS in section 5.4 illustrates, the proper chemistry of including all important species is always far more important than the proper physics of making activity corrections. [Pg.220]

B.A Cooke, Concentration polarization in electrodialysis-I. The electrometric measurement of interfacial concentration, Electrochim. Acta, 1961, 3, 307-317. [Pg.281]

McClelland, 1974). These values are also in agreement with proton activities derived from electrometric measurements (Janata and Jansen, 1972 Yates and McClelland, 1973). The assumption must be made that variations in aH+ are independent of the counterion. As Yates and McClelland (1973) point out, the ability to use log < h + with directly measured values of log yx and 7/x opens the way for estimating the free energy of solvation for many kinds of BH + onium ions in media where direct measurement would be difficult or impossible. [Pg.99]

This section contains a discussion of pH scales and the electrometric measurement of pH, tables of assigned pH values for various buffered solutions, and tables (about 600 entries) of thermodynamic acid dissociation constants of weak organic acids (some as a function of temperature). [Pg.774]

In conclusion, intracellular [K" ] as measured indirectly by chemical methods generally yielded high values which resulted in the overestimation of the K" " equilibrium potential. To account for an Ej greater than E across the peritubular cell boundary, an active K" influx mechanism was postulated. However, the direct electrometric measurement of intracellular potassium yields the true value of E. This study has shown that E = E for both the peritubular and the luminal cell membranes. In other words, both the luminal and peritubular cell membranes act as potassium electrodes. Therefore, as in skeletal muscle (Khuri et aZ.j 1972), a Donnan-type equilibrium holds with respect to potassium ion passive distribution across both boundaries. [Pg.120]

Bjerrum N, Unmack A (1929) Electrometric measurements with the hydrogen electrode on mixtures of acids and bases with salt. The dissociation constants of water, phosphoric acid, citric acid and glycine. Kgl Danske Videnskab Selskab Math Fys Medd 9 5-206 Timberlake CF (1964) Iron-malate and iron-citrate complexes. J Chem Soc 5078 5085 Litchinsky D, Purdie N, Thomson MB, White WD (1969) A rigorous solution to the problem of interfering dissociation steps in the titration of polybasic acids. Anal Chem 41 1726 1730... [Pg.198]

An electrode widely used as a reference electrode of known potential in electrometric measurement of acidity and alkalinity, corrosion studies, voltammetry, and measurement of the potentials of other electrodes. [Pg.469]

As it is well known, potentiometry is the simplest and most often used electrometric measuring technique. In potentiometry the potential difference that is the electromotive force (often called open circuit potential) between the measuring and the reference electrodes is measured using a high resistance millivolt meter, like a pH meter. The concentration of the measured species is determined upon calibration. [Pg.290]


See other pages where Electrometric measurement is mentioned: [Pg.828]    [Pg.942]    [Pg.677]    [Pg.677]    [Pg.678]    [Pg.678]    [Pg.1097]    [Pg.1211]    [Pg.15]    [Pg.15]    [Pg.339]    [Pg.265]    [Pg.69]    [Pg.474]    [Pg.76]    [Pg.78]    [Pg.313]    [Pg.313]    [Pg.253]    [Pg.430]    [Pg.1576]    [Pg.22]    [Pg.374]    [Pg.34]    [Pg.955]   
See also in sourсe #XX -- [ Pg.8 , Pg.115 ]




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