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Gram-equivalent, definition

It is also sometimes simply referred to as the gram-equivalent . However, GEW has two distinct definitions for neutralization as well as as oxidation-reduction reactions as stated below ... [Pg.42]

John Dalton s table of elements shown in Figure 1.37 include equivalent masses or gram equivalent masses. It is the mass of one equivalent, that is the mass of a substance which will react with one gram of hydrogen. Equivalent masses were a useful generalization of the law of definite proportions. [Pg.25]

The concentration of acid in a suspension of ion exchange resin (m ) is usually expressed as gram-equivalents (or moles) of acid groups per kg of solvent added to the dry resin. This definition is similar to that used by Haskell and Hammett [13], who also defined the efficiency of the resin (q) as the ratio of the catalytic rate of an acid-catalysed reaction in the presence of ion exchanger to the catalytic rate of the same reaction without ion exchanger but in presence of the same bulk concentration (m ) of hydrogen ion, added as hydrochloric acid. [Pg.412]

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. [Pg.330]

Definition A single unit of RGI. One GGE unit is equivalent in glycemic effect to one gram of glucose. For example, one microwaved potato (Table 13.2) with a relative glycemic impact (RGI) of 15 GGE would... [Pg.377]

It is important to note that in the various studies reviewed in the preparation of this document, dose levels have been presented by those authors in several ways. In order to facilitate comparisons among studies, these levels have generally been converted to an equivalent dose in microcuries (p Ci) and kilo-Becquerels (kBq). The historical definition of one curie is the disintegration rate exhibited by one gram of radium. There are 0.027 pCi per kBq. In this document, comparisons are usually made between total administered amounts of radioactivity, in pCi/kg and kBq/kg, instead of using a daily dosage level. [Pg.22]

Specification sheets will often give the equivalent weight of the polyol in terms of the hydroxyl number ("OH" value). The hydroxyl number is defined as "the number of milligrams of potassium hydroxide (KOH) equivalent to the hydroxyl content of 1.0 grams of polyol." Manipulation of this definition gives the follow equation ... [Pg.227]

Formally, percent by weight to volume is defined as grams of solute per 100 mL of solution. There are two mathematically equivalent statements of this definition ... [Pg.195]

Salinity was first rigorously defined by Knudsen (1902, p. 28) as the weight in grams of the dissolved inorganic matter in one kilogram of seawater after all bromide and iodide have been replaced by the equivalent amount of chloride and all carbonate converted to oxide. In 1978, the JPOTS decided that a new definition was needed for salinity that was based more on a salinity/conductivity ratio and was termed the practical salinity scale. [Pg.82]

One coulomb C or one ampere-second is a unit of quantity of electricity (electric charge) required to deposit 0,001118 grams of silver from a solution of silver nitrate regardless of the time during which the current passed through the electrolytic cell. This definition means that a current of one ampere represents a quantity of electricity equivalent to one coulomb per second. [Pg.25]

The heat transfer was originally measured in units of calories, where one calorie was defined as the quantity of energy required to raise one gram of pure water from 14.5 to 15.5 °C at one atmosphere. This definition has been supplanted by the introduction of the joule, which represents the energy specified by the conversion factor 1 cal = 4.184 joules. One joule is also equivalent to the energy developed in a circuit by an electric current of one ampere flowing through a resistance of one ohm (driven by a potential difference of one volt) in one second. [Pg.80]

The major use of equivalents stems from its definition. Once you define the number of equivalents in a certain mass of a substance, you do not need to write the equation for its reaction. That equation has already been used in defining the number of equivalents. Thus, a chemist can calculate the number of equivalents in a certain mass of substance, and technicians can subsequently use that definition without knowing the details of the reaction. The equivalent mass of a substance is the mass in grams of one equivalent of the substance. [Pg.99]

The mole (abbreviated mol) is defined as the amount of a substance comprising as many elementary units as there are atoms in 12 g of The definition of the mole is equivalent to the statement that the mass of one mole of a pure substance in grams is numerically equal to its molecular weight calculated from the standard table of atomic weights, in which the atomic weight of carbon is given as 12.01115. This number differs from 12 because it applies to the natural isotopic mixture of carbon rather than to pure... [Pg.7]


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See also in sourсe #XX -- [ Pg.4 ]




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Gram-equivalent

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