Determination of equivalent

Two useful characterization applications involving acid-base titrimetry are the determination of equivalent weight, and the determination of acid-base dissociation constants. 

Potcntiomctric Titrations In Chapter 9 we noted that one method for determining the equivalence point of an acid-base titration is to follow the change in pH with a pH electrode. The potentiometric determination of equivalence points is feasible for acid-base, complexation, redox, and precipitation titrations, as well as for titrations in aqueous and nonaqueous solvents. Acid-base, complexation, and precipitation potentiometric titrations are usually monitored with an ion-selective electrode that is selective for the analyte, although an electrode that is selective for the titrant or a reaction product also can be used. A redox electrode, such as a Pt wire, and a reference electrode are used for potentiometric redox titrations. More details about potentiometric titrations are found in Chapter 9. 

The third protocol is to determine the level of drug use and calculate equivalent doses of phenobarbital (Table 3-5). The patient is stabilized on this dose (divided into administration every 8 hours) for a few days, and then the dose is tapered by 10% daily. Although this method has its proponents, the determination of equivalency is an approximation, drug histories are unreliable, and mixed sedative-hypnotic dependence will complicate the procedure. 

Faraday s Electrochemical Laws and the Determination of Equivalent Weights. (With Rosemary Gene Ehl). J. Chem. Educ.,... 

From Eq. (a) it is evident that each molecule of FeS04, upon oxidation, happens to lose one electron. Hence, one mole of FeS04 loses 6.02 x 1023 electrons which is equivalent to 1 Faraday or 96,500 C. Thus, in electrochemical determination of equivalence point the quantity of electricity is almost identical with that required to reduce 1 mole of Ce(S04)2. It follows from here that 1 mole of FeS04 and 1 mole of Ce(S04)2 are chemical equivalents. In other words, 1 g of H, acting as a reducing agent, loses electrons equivalent to 96,500 C. 

Table 10.1. Comparison of full-width at half-maximum (nm) of two Nd emission lines with Th concentration of different natural monazites and determination of equivalent annealing fictive temperature (Madagascar sample considered as reference material), (nd not determined) (age Scharer and Deutsch 1990 Paquette et al. 1994 Seydoux-GuiUaume et al. 2002b Scharer et al. 1994)...

G. Papanastasiou and I. Ziogas, Simultaneous Determination of Equivalence Volumes and Acid Dissociation Constants from Potentiometric Titration Data, Talanta 1995,42, 827. 

Normal endorsement will be based on findings in the inspection report as they are measured against the importing country s own laws and based on the determination of equivalence in light of the experience gained. FDA expects that it will be able to normally endorse inspection reports received from authorities listed as equivalent. 

Gran G. (1952) Determination of equivalence point in potentiometric titration Part II. Analyst 77,661-671. 

EXPERIMENT 2.6 ANALYSIS OF COBALT COORDINATION COMPOUNDS IV—DETERMINATION OF EQUIVALENT WEIGHT BY ION EXCHANGE CHROMATOGRAPHY1-5... 

In 1995 the Federal Circuit addressed basic issues concerning the doctrine of equivalents and held that (l)the determination of equivalents is a fact issue to be resolved by the jury ... 

G. Gran, Determination of Equivalent Point in Potentiometric Titrations, Acta Chem. Scand., 4 (1950) 559. 

EPA has established a procedure to allow use of alternative control measures instead of some of the control measures specified in SNURS. This was necessary because in some instances a SNUR s reliance on respirators may conflict with the Occupational Safety and Health Administration s preference for engineering controls, which would be an alternative control measure. If these alternative control measures are implemented the use will not be a significant new use. EPA will entertain applications from manufacturers, importers or processors who propose alternatives to measures to control worker exposure or environmental releases.Applicants must submit a request to EPA for a determination of equivalency to ... 

The request for a determination of equivalency must include the submitter s name, the chemical identity of the SNUR substance, a citation to the SNUR in the Code of federal Regulations, a detailed description of the planned use, specifications of the alternative worker exposure or environmental release control measure, an analysis justifying why the alternative provides substantially the same degree of protection as the control measure specified in the SNUR, and all previously unsubmitted test data on the SNUR... 

EPA has proposed electronic filing regulations and if these go into effect then requests for determinations of equivalency filed after the effective date must be made using the ePMN software, and may be filed on paper, through CD, DVD, or EPA s Central Data Exchange (CDX) for one year after the effective date of the new rules, and thereafter must be submitted via CD, DVD, or CDX for the next year, and then only through CDX. ... 

The regulations require EPA to review requests for determinations of equivalency within forty five days, and mail determinations back to the submitter. The submitter can only begin to manufacture, import or process for a use involving the alternative control measures if the EPA determines that the alternative control measures provide substantially the same degree of protection as the SNUR controls. Any deviation from the terms of the EPA s approval will be a significant new use. 

Several of the standardized significant new uses expressly contemplate alternative control measures, subject to approval by the EPA. For example, if a mixture has two or more SNUR substances in it, the label must include the most protective measures, but the label may include alternative control measures if the EPA has provided a determination of equivalency. ... 

Simple formulae for the determination of equivalent springs and dampers for soil-structure interaction can be found in seismic engineering textbooks (Castellani et al., 2000 Roesset, 1980). Some examples are also included in the section on soil-structure interaction on p. 173. 

The determination of asphalt overlay thickness on rigid pavements is conducted in exactly the same way as for asphalt overlay on a flexible pavement use of conversion factors, determination of equivalent thickness pavement and determination of full-depth pavement (see Section 15.17.3). 

Petersen, R. L., and B. C. Cochran. 1995. Wind Tunnel Determination of Equivalent Refinery Roughness Patterns, CPP Report 94-1152, CPP, Fort CoUins, CO. 

Homberg s quantitative experiments on the neutralisation of acids and bases are the first determinations of equivalent weights. Simon Boulduc (d. Paris, 1729 demonstrator in the Jardin du Roi) tried in 1698 to find the... 

Akzo Chemie Method VV3.001 Ethoxylated fatty amines/diamines Determination of equivalent mass. 

There are a number of requirements specified for nonlisted PLCs. According to A8.3 (P37) of NFPA 87 (2015) Controls that meet the perfomumce-based requirements of standards such as ANSI/ISA 84-00.01 Application of Safety Instrumented Systems for the Process Industries, can be considered equivalent. The determination of equivalency involves complete conformance to the safety lifecycle including risk analysis, safety integrity level selection, and safety integrity level verification, which should be submitted to the authority having jurisdiction. 

The above example shows the correspondence between penetration rate and current density for a metal. A similar correspondence between the penetration rate and current density for alloys can be established. However, it would require the determination of equivalent weight (M/n) for the alloy. 

Derivatives.. S-Benzylthiuronium salt determination of equivalent weight (both as for carboxylic acids, pages 123, 124). 

Huang BC, Leung AYT, Lam KL, Cheung VK (1996) Analytical determination of equivalent modal... 

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