Freezing point depression measurements

Boiling-point elevation and freezing-point depression measurements have demonstrated that at all concentrations in THF and at low concentrations in ether (up to 0.1M) Grignard reagents prepared from alkyl bromides and iodides are monomeric, that is, there are few or no molecules with two magnesium atoms. Thus, part of the Schlenk equilibrium is operating... 

A unitless correction factor that relates the relative activity of a substance to the quantity of the substance in a mixture. Activity coefficients are frequently determined by emf (electromotive force) or freezing-point depression measurements. At infinite dilution, the activity coefficient equals 1.00. Activity coefficients for electrolytes can vary significantly depending upon the concentration of the electrolyte. Activity coefficients can exceed values of 1.00. For example, a 4.0 molal HCl solution has a coefficient of 1.76 and a 4.0 molal Li Cl has a value of... 

Characterization of the AlMe3—MeCl System by NMR. It appears that the AlMe3 in methyl chloride system has not been investigated previously by NMR spectroscopy. In related research by other workers, freezing point depression measurements of AlMe3 in benzene solution indicated the predominant presence of dimers—i.e. (13) ... 

The mechanism of extraction in tracer rare earth concentrations using HDEHP was investigated by Peppard et al. (7,8,9). Freezing-point depression measurements of toluene by the addition of HDEHP showed that HDEHP is dimeric in solution (9). On the basis of all their findings... 

Freezing point depression measurements furnish another convenient approach to determine the activity of the solvent. Eqs. (3.13.1,4) may be taken over without change because we have not had occasion to refer to the ionic dissociation process. 

Pentaethoxyuranium is a dark-brown, mobile liquid with a density of 1.71 g/cm3 at 25°.2 The liquid boils at 123° at 0.001 torr and is thermally stable below 170°. The compound is readily hydrolyzed and is oxidized by dry oxygen (in the presence of excess NaOC2Hs) to hexaethoxyuranium.2 Pentaethoxyuranium has a dimeric structure at room temperature as determined by freezing-point depression measurements in benzene.2 It is miscible with ethanol, diethyl ether, benzene, petroleum ether, ethyl acetate, carbon tetrachloride, chloroform, carbon disulfide, pyridine, dioxane, and nitrobenzene. The proton magnetic... 

The Nitryl Ion, NO The stem nitric acid-sulfuric acid, commonly known as mixed acid, is the most important nitrating medium from a practical standpoint and is probably also the best understood. There is a large body of evidence that supports the belief that nitric acid exists in strong sulfuric acid as the nitryl ion, N02 . From freezing-point depression measurements, the Van t Hoff t factor (the number of particles generated by one molecule of solute) of nitric acid in sulfuric acid is found to be 4, which indicates that the ionization of nitric acid can be represented by the equation... 

What is formed when a solution for a freezing-point depression measurement freezes ... 

Compare the experimental molecular weight of aspirin as calculated from freezing-point depression measurements with that calculated from NaOH titration data. Explain the difference. 

The state of cure of the phases in a blend can be determined from changes in the magnitude of the damping peaks (Runt and Martynowicz, 1985) and from freezing-point-depression measurements on swollen networks. Keith and... 

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