Concentration expression equivalents

In the older literature, C is the concentration in equivalents per liter. The volume of the solution in cubic centimeters per equivalent is equal to 1000/C, and A = 1000 k/C, the units employed in Table 8.32 cm equiv ]. The formula unit used in expressing the concentration must be specified ... 

Smoke stain When a certain quantity of dirty air is passed through a filter paper, the degree of staining on the paper is measured and expressed as a concentration of equivalent standard smoke by means of an optical reflectometer. 

There might be various reasons that lead to finding an apparent instead of the true activation energy. The use of power-law kinetic expressions can be one of the reasons. An apparent fractional reaction order can vary with the concentration, i.e. with conversion, in one experimental run. Depending upon the range of concentrations or, equivalently, conversions, different reaction orders may be observed. As an example, consider the a simple reaction ... 

In the relationship shown above, A and B are constants depending on temperature, viscosity of the solvent, and dielectric constant of the solvent, C is the concentration expressed in gram equivalents per liter, and Ac represents the equivalent conductance of the solution. A0 is the equivalent conductance at infinite dilution - that is, at C = 0, when the ions are infinitely apart from one another and there exists no interionic attraction, a represents the degree of dissociation of the electrolyte. For example, with the compound MN... 

The initial near-parallel displacement of the curves in Figure 1.26B raises the question of whether the Schild equation would be obeyed under these conditions. If we consider the two concentrations of agonist that give equal responses before and during the action of the antagonist ([A] and r[A], respectively, where r is the concentration ratio) and repeat the derivation set out in Section 1.5.2 (but using Eq. (1.55) rather than (1.49)), we find that the expression equivalent to the Schild equation is ... 

We can define a critical segment concentration s equivalent to pc provided we allow for the total number of links. If we ignore the constants in the expression we obtain ... 

Young et al. [43] chose an alternative approach to prediction of ultimate pH. They measured the concentration of the muscle glycogen responsible for lactic acid formation. This was done immediately after slaughter. The glycogen concentration, expressed as glucose equivalents per gram of muscle, has a curvilinear relationship to ultimate pH (Fig. 28.1). 

Here, I and i are the electric current and the current density passing through a cell pair, A is the cell area, f) is the volume flow, C is the concentration expressed in equivalent per volume, F is the Faraday constant, and E, the current utilization. The subscripts cell refers to the diluate cell, and the superscripts d and f refer to diluate and feed solution, respectively. 

Fig. 2. Quantitative analysis of organs and tissues. The concentrations (expressed as drug equivalents/g) were calculated by dividing the measured radioactivity concentrations by the specific radioactivity of the administered compound. Upper plot shows the concentration-time-profile, lower plot shows the concentrations at the time of Cmax.

Optical (Specific) Rotation Transfer an accurately weighed amount of sample, equivalent to about 100 mg of total tocoph-erols, into a separator, and dissolve it in 50 mL of ether. Add 20 mL of a 10% solution of potassium ferricyanide in a 1 125 sodium hydroxide solution, and shake for 3 min. Wash the ether solution with four 50-mL portions of water, discard the washings, and dry over anhydrous sodium sulfate. Evaporate the dried ether solution on a water bath under reduced pressure or in an atmosphere of nitrogen until about 7 or 8 mL remains, and then complete the evaporation, removing the last traces of ether without the application of heat. Immediately dissolve the residue in 5.0 mL of isooctane, and determine the optical rotation. Calculate the optical rotation [see Optical (Specific) Rotation, Appendix HB], using as c the concentration expressed as the number of grams of total tocopherols, as determined in the Assay (above), in 100 mL of the solution. 

Equivalent concentration and normality. This method of expressing concentrations is analogous to molar concentrations, with the solute expressed in terms of equivalents. One problem that is often encountered is the conversion of a molar concentration to equivalent concentration. Let [C] be the molar concentration of any substance, where the symbol [ ] is read as the concentration of. Convert this to equivalent concentration. 

CaC03] is an equivalent molar concentration expressed in terms of moles of CaC03. Thus, to get the equivalent calcium carbonate mass concentration, it must be multiplied by CaC03 = 100. Therefore,... 

The direction in which any given sorbate molecule moves is random. However, the overall effect is motion from a region of higher surface concentration to a region of lower surface concentration and an expression equivalent to (Eq. [3a]) is applicable. 

This is Henry s law, and AT, is the Henry s law constant, which must be measured for each gaseous compound of interest that dissolves in water. The law states that the tendency of a volatile compound dissolved in water to escape to another phase (air, surface, etc.) is proportional to its mole fraction in the water. Henry s law behavior is followed most closely as x, approaches zero, that is, in very dilute solutions of the volatile compound. As x, approaches zero, the mole fraction becomes linearly proportional to the more conventional measure of concentration, molarity, so that equation 1.40 can be expressed equivalently with molarity replacing mole fraction. 

Acids will dissociate into hydrogen ions, i.e., protons, and their matching anions. Bases will dissociate into a cation and a hydroxyl anion. If the acid or base is a strong acid or strong base, then the dissociation is complete. Weak acids and weak bases dissociate only partially. How much is defined by the dissociation constant of the acid or base. When expressed as the negative logarithm of the proton concentration in equivalents/liter, it is called the pK of the acid or base. Therefore, in a solution of a weak acid, three participants are present proton, matching anion, and the undissociated parent weak acid. Similarly, a solution of a weak base contains a cation, a hydroxyl anion, and the undissociated parent base. How much of each is defined by the pH of the solution and the pK of the respective acid or base The Henderson-Hasselbalch equation defines the relationship ... 

Each animal was sacrificed by captive bolt after the appropriate withdrawal interval (4, 6, 14 and 28 days after the 2nd dose) and processed as in an abattoir. The entire liver, kidneys and udder were excised and 1-2 kg samples of muscle from both the flank and the udder diaphragm and 1-2 kg samples of fat from the abdominal area were collected. Each organ and tissue was minced and processed three times through a commercial meat grinder to prepare respective homogenate samples. Sub-samples (200-300 mg) were prepared in triplicate for total residue analysis. Total radioactivity concentrations, expressed as pirlimycin free base equivalents, were determined by direct liquid scintillation counting (liquids) or combustion analysis (solids) following standard techniques. 

Substances with a saturated-air concentration below their TLVs do not pose a significant vapor inhalation hazard. Vapor pressures can be roughly converted to saturated-air concentrations expressed in parts per million by multiplying by a factor of 1300. This Is equivalent to dividing by 760 mm Hg and then multiplying the result by 1 million to adjust for the original units of parts per million (a pressure of 1 equals 760 mm Hg) ... 

Table 3.4 provides data about the specific and equivalent electrical conductivities of sulfuric acid solutions of various concentrations, expressed in different units [2]. 

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