Chemically equivalent

See chemical equivalent, equivalent conductivity The specific conductance multiplied by the volume (ml) which contains 1 g equivalent of the electrolyte. 

If the two structures produced by mental replacement of two different hydrogens in a molecule by a test group are the same the hydrogens are chemically equivalent Thus... 

Normality makes use of the chemical equivalent, which is the amount of one chemical species reacting stoichiometrically with another chemical species. Note that this definition makes an equivalent, and thus normality, a function of the chemical reaction in which the species participates. Although a solution of 1T2S04 has a fixed molarity, its normality depends on how it reacts. 

See Section 2B.2 for a review of chemical equivalents and equivalent weights. 

Although each production process yields ash that is essentially chemically equivalent, the various products differ ia physical properties and ia contaminants as shown ia Table 6. Hopper cars, pneumatic tmcks, supersacks, and multiwaH kraft bags with polyethylene liners are the usual shipping containers. 

Various expressions have been derived from which corresponding rates for alloys can be calculated. AH these procedures are based on calculating an effective value for the chemical equivalent of the alloy. Thus for Nimonic 75, a typical nickel alloy used in the aircraft industry, a chemical equivalent of 25.1 may be derived (4). The Nimonic alloy is given to have, on a basis of wt %, 72.5 Ni, 19.5 Cr, 5.0 Ee, 0.4 Ti, 1.0 Si, 1.0 Mn, and 0.5 Cu (see Nickel and... 

Bioavailability, Bioequivalence, and Pharmacokinetics. Bioavailabihty can be defined as the amount and rate of absorption of a dmg into the body from an adrninistered dmg product. It is affected by the excipient ingredients in the product, the manufacturing technologies employed, and physical and chemical properties of the dmg itself, eg, particle size and polymorphic form. Two dmg products of the same type, eg, compressed tablets, that contain the same amount of the same dmg are pharmaceutical equivalents, but may have different degrees of bioavailabihty. These are chemical equivalents but are not necessarily bioequivalents. For two pharmaceutically equivalent dmg products to be bioequivalent, they must achieve the same plasma concentration in the same amount of time, ie, have equivalent bioavadabihties. 

The main producers of organic accelerators for mbber vulcanization are shown in Table 3. This table is not meant to be completely comprehensive, but rather to indicate the principal historical suppHers to the mbber industry. Most producers offer chemical equivalents in the largest-volume products. Within the range of smaHer-volume specialty accelerators, chemical equivalents become less common. Each producer may offer different products to achieve the same purpose of rapid cross-linking, resistance to thermal degradation, or other performance characteristics. Many offer proprietary blends of accelerators. 

Ion exchange may be thought of as a reversible reaction involving chemically equivalent quantities. A common example for cation exchange is the familiar water-softening reaction... 

Mixed cation and strong-hase anion (chemical-equivalent mixture) 40 max. (16) 1.2 (47) 50 (122) 0.2-0.. 35 (based on mixture) Same as cation and anion individually... 

Chemical equivalence atomic nuclei in the same chemical environment are chemically equivalent and thus show the same ehemieal shift. The 2,2 - and 3,3 -protons of a 1,4-disubstituted benzene ring, for example, are ehemically equivalent because of molecular symmetry. 

In all types of NMR spectra H, C, N), 2-azidopyrimidine (2) can be distinguished by the symmetry of its pyrimidine ring (chemical equivalence of 4-H and 6-H, C-4 and C-6, N-1 and N-3) from tetrazolo[l,5-a]pyrimidine ( ) because the number of signals is reduced by one. Hence the prediction in Table 30.1 can be made about the number of resonances for the -butyl derivative. 

The epoxide equivalent is a measure of the amount of epoxy groups. This is the weight of resin (in grammes) containing 1 gramme chemical equivalent epoxy. For a pure diglycidyl ether with two epoxy groups per molecule the epoxide... 

Inspection of the citrate structure shows a total of four chemically equivalent hydrogens, but only one of these—the pro-/J H atom of the pro-i arm of citrate—is abstracted by aeonitase, which is quite stereospecific. Formation of the double bond of aconitate following proton abstraction requires departure of hydroxide ion from the C-3 position. Hydroxide is a relatively poor leaving group, and its departure is facilitated in the aeonitase reaction by coordination with an iron atom in an iron-sulfur cluster. 

Extensions to other reactions and to other aza-naphthalene systems is obvious. The chemical equivalence between formally identical positions in all possible situations must be established experimentally. In this connection, caution should be used because for some of the above positions steric hindrance may become an important factor in determining the overall reactivity. 

Both CSs and CSs were also successfully generated by the fragmentation of ionized 4,5-dioxo-2-thioxo-l,3-dithione (65) and 2-thioxo-l,3-dithiole (66) (90JA3750). Tire three sulfur atoms in the anion and cation radicals were chemically equivalent, suggesting that they take the D h (or C2u) form (67 or 68). On the other hand, under similar conditions, 3-thioxo-1,2-dithiole (69) yielded two isomeric cation radicals the (or 2 ) form and the carbon disulfide 5-sulfide form (70). Ab initio calculations on three electronic states of CS3 at the 6-31G -l-ZPVE level indicated that the C21, form (68) was more stable than the carbon disulfide 5-sulfide form (70) in the neutral (both singlet and triplet states) and the anion radical states, but 68 was less stable than 70 in the radical cation state. 

The equivalent weight of an ion (or an element) is the ratio of its formula weight to its valence. According to an alternative definition that is also suitable for compounds, an equivalent weight represents the amount of a substance which will react with one atomic weight of hydrogen or its chemical equivalent. 

The last definition has widespread use in the volumetric analysis of solutions. If a fixed amount of reagent is present in a solution, it can be diluted to any desired normality by application of the general dilution formula V,N, = V N. Here, subscripts 1 and 2 refer to the initial solution and the final (diluted) solution, respectively V denotes the solution volume (in milliliters) and N the solution normality. The product VjN, expresses the amount of the reagent in gram-milliequivalents present in a volume V, ml of a solution of normality N,. Numerically, it represents the volume of a one normal (IN) solution chemically equivalent to the original solution of volume V, and of normality N,. The same equation V N, = V N is also applicable in a different context, in problems involving acid-base neutralization, oxidation-reduction, precipitation, or other types of titration reactions. The justification for this formula relies on the fact that substances always react in titrations, in chemically equivalent amounts. 

Rule 1 Chemically equivalent protons do not show spin-spin splitting. The equivalent protons may be on the same carbon or on different carbons, but their signals don t split. 

Three C-H protons are chemically equivalent no splitting occurs. 

The quantities 2 mol of N2H4,1 mol of N204,3 mol ofN2, and 4 mol of H20 are chemically equivalent to each other in this reaction. Hence they can be used in conversion factors... 

An experimental nm had been conducted to study the effect of airflow rate in the 3 litres aeration wastewater treatment tank. Nutrients were added in the treatment tank to ensure sufficient bacterial growth. In each experiment, the cell optical density, COD and die concentration of chemicals equivalent to carbohydrates were monitored for the duration of aeration. 

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