Mole ratio, definition

Definitions ctr, resonance constant cti, field constant a = or + ai. Reaction mole ratio of Ib/Ph-R/aluminum chloride = 1 20 0.1. 

Phase diagrams from freezing point depressions show true compound formations for simpler amides—e.g., water-N-methylacetamide forms a compound at a mole ratio of 2 to 1, water-N,N-dimethylacetamide at 3 to 2 and 3 to 1, and water-N-methylpyrrolidone at 2 to 1. The heats of mixing and heat capacities at 25°C. of a number of water-amide systems were determined. All mixing curves were exothermic and possess maxima at definite mole ratios, while the heat capacities for the most part show distinct curvature changes at the characteristic mole ratios. Both experimental results point to the stability of the particular complexes even at room temperature. This is further supported by absolute viscosity studies over the whole concentration range where large maxima occur at these same mole ratios for disubsti-tuted amides and N-substituted pyrrolidones. 

Heat Capacities. The heat capacities (Cp in cal./mole-°C., not shown here) exhibit some unusual features, in that they show marked curvature changes at the characteristic mole ratios found thus far for each of the respective amides or pyrrolidones, again rendering it likely that definite stoichiometric complexes occur in the amide-water mixtures. 

The above definition of S is employed independently of the actual kinetic order of the product-determining step. Solvolytic reactions may be of higher kinetic order, or it could be argued that their kinetic order is ill-defined. There is no need to derive Equation 2.9 - it can stand alone as the definition of S. To illustrate how the equation works, suppose that the solvent is an equimolar mixture of alcohol and water, so the solvent mole ratio is 1.0. If the product mole ratio is also 1.0, then S = 1.0, and the product-forming reactions are unselective (so log S = 0 for an unselective reaction). If twice as much ether is formed as alcohol in an equimolar solvent mixture, then S = 2. In practice, many solvent compositions are employed, and the equation corrects automatically for variations in solvent composition. 

Inst as compounds have definite ratios of elements, chemical reactions have definite ratios of reactants and products. Those ratios are used in Section 10.1 to calcnlate the number of moles of other substances in a reaction from the nnm-ber of moles of any one of the snbstances. Section 10.2 combines information from Section 10.1, Chapter 7, and elsewhere to explain how to calcnlate the mass of any substance involved in a reaction from the mass of another. Section 10.3 demonstrates how to work with qnantities in nnits other than moles or masses when finding quantities of reactants or prodncts. Section 10.4 shows how to calcnlate the quantities of snbstances involved in a reaction even if the quantities of reactants present are not in the mole ratio of the balanced equation. Section 10.5 covers the calculation of the percentage yield of a product from the actual yield and the theoretical yield, based on the amonnt(s) of reactant(s). Section 10.6 explains which of these types of calcnlations can and cannot be done with net ionic equations. 

The units parts per million (ppm) and parts per billion (ppb) are used to express the concentrations of trace species (species present in minute amounts) in mixtures of gases or liquids. The definitions may refer to mass ratios (usual for liquids) or mole ratios (usual for gases) and signify how many parts (grams, moles) of the species are present per million or billion parts (grams, moles) of the mixture. If y, is the fraction of component i, then by definition... 

The work of Rammon ( ) characterized UF resins prepared from UF concentrates. One of his observations was that cured UF resins are crystalline. Rammon s observations were subsequently confirmed by Stuligross and Koautsky. This is somewhat surprising in that a cross-linked material, by definition, is not crystalline in nature. The cross-links should serve to disrupt the structural regularity required to permit a crystal to form. While a study of the crystalline nature of UF resins was not the major thrust of Rammon s research, a brief survey of the phenomenon was made. Rammon showed that all UF resins below a mole ratio of 1.43 gave distinct powder... 

Mjj Calc, number average molecular weights I see the footnotes in Table I for definitions) are in good agreement. For the third reaction in which R2 is the n-C Hg group, the observed M, was less than half of that expected on the oasis of the monomer-to-initiator mole ratio. 

Problem 10.5 The experimental data available in the literature on the equilibrium polymerization of caprolactam (CL) are of the type a known mole ratio m of H2O to CL is charged in a vessel the vessel is brought to a definite temperature and polymerization is carried out to equilibrium. When equilibrium is reached, the value of DP and [M] (or conversion p) are determined. 

Table 16.3 shows some possible forms of mass transfer coefficient definitions and the relationships between the coefficients based on EMD and UMD. In addition to Ky and Ky coeflScients, we can also define Ky and Kx coefficients based on mole ratio f(T— Tj) and (Xj — X)] driving forces. 

If we can determine the moles of HCl, we can then nse the definition of molarity to calcnlate the volnme of HCl needed. From the volume and molarity of NaOH or Ba(OH)2, we can calculate moles of NaOH or Ba(OH)2. Then, using the mole ratio from the balanced eqnation, we can calculate moles of HCl. 

The "parts-per" notation is a unit that deals with very small traces of species within a mixture of gases or liquids. Parts-per million (ppm) and parts-per billion (ppb), as well as parts-per trillion (ppt) (American definition of trillion 10 ), refer to mass or mole ratios and communicate how many parts of the species are present-per million, billion, or trillion parts of the mixture. Generally mass ratios are used when dealing with liquids and mole ratios are used when dealing with gases, though either kind of ratio can be used for whichever phase a chemical is in (ratios are discussed in a later chapter). 

Synonyms Aluminosilicic acid, sodium salt Aluminum sodium silicate Silicic acid, aluminum sodium salt Sodium aluminosilicate Sodium aluminum silicate Sodium feldspar Zeolite Zeolites Definition Series of hydrated sodium aluminum silicates produced by reaction of sodium silicate and kaolinite clay Formula NajO AI2O3 SiOa with mole ratio = 1 1 13.2 Properties Wh. fine amorphous powd. or beads, odorless and tasteless insol. in water, alcohol, org. soivs. partly sol. in strong acids and alkali hydroxides 80-100 C pH 6.5-10.5 (20% slurry)... 

Method of Continuous Variations (Job s Method). In this method, a series of solutions are prepared in which, to take metal eomplexation formation as an example, the sum of the concentrations of the metal and ligand is held constant, as the mole ratio of M to L is varied from 0.0 to 1.0 in steps of 0.1 (or smaller). As with the mole ratio method, the data is seen to form two linear segments which intersect at a point that reveals the composition of the complex. For ML, this point is at mole ratio 0.5 for ML2, the lines intersect at 0.33[M] [L], etc. The differences in absorbance between the values on the hypothetical extrapolated lines and the experimental values provide the basis of calculating the P value. A comparison of Figures 19.3 and 19.4 show that Job s method gives clearer definition of complex composition when p values are small. 

This is an acid base equilibrium under the Franklin definition. The [AI2CI7]" species is the acid and the Cl is the base. Note that this is an aprotic equihbrium. Therefore if the mole ratio of [Q-mimjCkAlCla is greater than, less than, or exactly equal to 50 50, flic solvent behavior can be described as Franklin basic, Franklin acidic, or neutral. 

Complexes of polymeric acceptors and monomeric donors are also effective in inducing discotic PLCs. This was shown, in particular, for a main chain polyester into which TNF was incorporated, mixed with a triphenylene derivative [73]. In order to avoid phase separation, the donor concentration must exceed the acceptor concentration by a mole ratio of at least 3 1. It was also demonstrated that the alkyl spacer length in the main chain can be critical to the definition and stability of the discotic mesophase obtained. As illustrated in Figure 3.32, spacer lengths which are either too short or too long can inhibit the incorporation of the polymeric acceptor into the donor columns, the... 

In a chemical reaction, there is a definite ratio between the number of moles of a particular reactant or product and the number of moles of any other reactant or product. These ratios are readily seen by simply examining the coefficients in front of the reaction species in the chemical equation. Normally, a stoichiometric calculation is performed to relate the quantities of only two of the reaction participants. The objective may be to determine how much of one reactant will react with a given quantity of another reactant Or, a particular quantity of a product may be desired, so that it is necessary to calculate the quantity of a specific reactant needed to give the amount of product To perform stoichiometric calculations involving only two reaction participants, it is necessary only to know the relative number of moles of each and their molar masses. The most straightforward type of stoichiometric calculation is the mole ratio metiiod defined as follows ... 

Hint Use mole ratios to convert separation factor definitions to Xn( ) =... 

The formation of coordination compounds between boron trifluoride and organic oxy-compounds are well known and a rule announced by Landolph states that boron trifluoride combines in a definite mole to mole ratio with aldehydes and ketones. 

Fig. 33. Solubility of hydrogen chloride in methanol at 25 C and low pressures pna- Mole fraction Nhq vs pHo and mole ratio jchq vs pna from the molality data of Schmid, Maschka, and Sofer (1964). A larger-scale plot of jcho vs Pho from the data at the lower end of the given Xho plot (below Xna = 0.03) is still definitely curved, concave upward.

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