Aqueous solution data temperature

In addition, data on the size, shape and solvation of the polymer particles in aqueous solutions at temperatures below and above the transition phenomena registered by HS-DSC have been obtained [42]. Table 2 shows the results of capillary viscometry and light scattering experiments for the fractions p and s of poly(NVCl-co-NVIAz) synthesized at 65 °C from the feed with the initial molar comonomer ratio equal to 85 15. Since fraction p precipitates from the aqueous solution at temperatures > 34 °C, its intrinsic viscosity can be determined only at 20 °C, whereas for the fraction s such measurements were possible above and below the temperatures of the HS-DSC-registered conformational transition. 

From the data in Fig. 4.8b, estimate the shift factors required to displace the data at 0 = 0.5 (consider only this point) so that all runs superimpose on the experiment conducted at 128 C at 0 = 0.5. Either a ruler or proportional dividers can be used to measure displacements. Criticize or defend the following proposition Whether a buffered aqueous solution of H2O2 and 1. containing small amounts of S2O3 and starch, appears blue or colorless depends on both the time and the temperature. This standard general chemistry experiment could be used to demonstrate the equivalency of time and temperature. The pertinent reactions for the iodine clock are... 

Hydrogen Chloride—Water System. Hydrogen chloride is highly soluble in water and this aqueous solution does not obey Henry s law at ah concentrations. Solubhity data are summarized in Table 5. The relationship between the pressure and vapor composition of unsaturated aqueous hydrochloric acid solutions is given in Reference 12. The vapor—Hquid equiHbria for the water—hydrogen chloride system at pressures up to 1632 kPa and at temperatures ranging from —10 to +70° C are documented in Reference 13. 

The specific heat of aqueous solutions of hydrogen chloride decreases with acid concentration (Fig. 4). The electrical conductivity of aqueous hydrogen chloride increases with temperature. Equivalent conductivity of these solutions ate summarized in Table 8. Other physicochemical data related to... 

Solubihty data ia water are given ia Figure 5 and ia Table 9, solution pH ia Table 10, and the solubiUty ia organic solvents is given ia Table 7. Heats of solution ia water have been determined (68,73). The pentahydrate, ia contact with its aqueous solution, is metastable with respect to the tetrahydrate (kernite) at temperatures above 58.2°C and metastable to borax decahydrate below 60.6—60.8°C. Kernite can be slowly crystallised from a near saturate... 

Cyanuric acid is a titrable weak acid (pffai — 6.88, pifa2 — H-40, pffas — 13.5) (10). The pH of a saturated aqueous solution of pure CA at room temperature is - 4.8. Thermodynamic properties of CA are given ia Table 1. Spectroscopic data are available (1 3). Proton nmr is of limited usefulness because of proton exchange and CA s symmetry and low solubiUty. Nuclear quadmpole resonance measurements ( " N) have been reported (12). 

In the two sets of results plotted in Fig. 34 no maximum is observed in either case within the range of temperature covered by the experiments nevertheless, in both cases the values appear to be tending toward a maximum lying just outside the experimental range, namely, at — 5.4°C for chloracetic acid, and at 53.9 for glycine. In 1934, Harned and Embree, surveying all the data (in Table 9) that had been obtained up to that time in aqueous solution, found a remarkable uniformity in... 

The conductivity of sodium dodecyl sulfate in aqueous solution and in sodium chloride solutions was studied by Williams et al. [98] to determine the CMC. Goddard and Benson [146] studied the electrical conductivity of aqueous solutions of sodium octyl, decyl, and dodecyl sulfates over concentration ranges about the respective CMC and at temperatures from 10°C to 55°C. Figure 14 shows the results obtained by Goddard and Benson for the specific conductivity of sodium dodecyl sulfate and Table 25 shows the coefficients a and p of the linear equation of the specific conductivity, in mho/cm, vs. the molality of the solution at 25°C. Micellization parameters have been studied in detail from conductivity data in a recent work of Shanks and Franses [147]. 

An aqueous solution of sodium sulfite, which was prepared at ambient temperature (or bisulfite, but free of thiosulfite) at a concentration of about 20%, is added to the reaction vessel. Usually 1.05-1.1 mol of the sulfite is required. The temperature is kept at 70-90°C with continuous stirring. The reaction can be finished when analytical data, e.g., content of free sulfite, are sufficient to fit the specification. Time required for the second step is around 30 min to 1 h. Finally the pH is adjusted to the desired level. 

Situation and Interpretation A series of peptides was assessed for stability in aqueous solutions. The data in files ARRHENX.dat X = 1, 2, or 3) was found in a doctoral thesis. " Figure 4.27 shows one case where a temperature range of 50°C was covered. (See also Table 4.25.)... 

Figure 4.27. Arrhenius analysis The right-hand panel shows the assay-vs.-time data for an aqueous solution of a peptide. The regression lines are for storage temperatures of 80°, 73°, 60°, 50°, 40°, and 30°C. The left-hand panel gives the ln(-slope)-vs.-l/T Arrhenius plot.

Wolery (1978) and Reed (1982, 1983) have indicated based on a computer calculation of the change in chemistry of aqueous solution and mineralogy during seawater-rock interactions that epidote is formed under the low water/rock ratio less than ca. 50 by mass. Humphris and Thompson (1978), Stakes and O Nell (1982) and Mottl (1983) have also suggested on the basis of their chemical and oxygen isotopic data of the altered ridge basalts that epidote is formed by seawater-basalt interaction at elevated temperatures (ca. 200-350°C) under the rock-dominated conditions. If epidote can be formed preferentially under such low water/rock ratio, the composition of epidote should be influenced by compositions of the original fresh rocks. 

Cloud Point Measurements Cloud points were recorded by the visual observation of aqueous solutions containing 1% W/V surfactant. The measurement defines the temperature at which the system under test shows a characteristic transitional change from a clear solution to an opalescent or cloudy state. All cloud points were recorded in both ascending and descending temperature cycles to ensure data confidence. The influence of salt and/or oils on the cloud point were systematically evaluated. 

In our laboratory, the sonication (20 kHz, 250 W, Air atm) of an aqueous solution of 0.1 M AgN03 for 10, 20 and 30 min produced turbidity as given in Table 9.1. Simultaneous measurement of rise in temperature and conductance was also recorded. The data of Table 9.1, however, are only qualitative and the author does not confirm to their quantitative figures. The same is true for similar tables in the subsequent sections of the chapter. 

We have already seen (p. 56) that the Ka, and hence pKa, value for an acid is not an intrinsic attribute of the species itself, because it varies from one solvent to another the value depending on the overall system of which the acid is a constituent. Values are normally quoted for aqueous solution, unless otherwise specified, because most data are available for that solvent. Most values are also quoted as at 25°, again because most data were obtained at this temperature. A constant temperature has to be specified as Ka, an equilibrium constant, varies with temperature. We have been concerned above with the relative... 

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