Molecular weight refractive index

Freesing point Molecular weight Refractive index N ... 

Flaeh point. Tag open cup Moiature content Molecular weight Refractive index at 26 C, n Sat point... 

Acidity ae acetic acid Boiling point at 760 mm. Hg Color, Pt-Co Diatillation range Flash point, open cup Freezing point Molecular weight Refractive index, 20 C, ns Solubility in water, 20 C Solubility of water in, 20 C Specific gravity, 20/20 C Suspended matter Vapor pressure, 20 C Viscosity, 20 C... 

E = constant in scaling equation G = Gibbs free energy h = scaling function defined by Equation 8 M = molecular weight n = index of refraction P = pressure... 

Characterization of a Petroleum Cut by Refractive Index, Density, and Molecular Weight (ndM method)... 

As in the case of density or specific gravity, the refractive index, n, for hydrocarbons varies in relation to their chemical structures. The value of n follows the order n paraffins < n naphthenes < n aromatics and it increases with molecular weight. 

With the accumulation of results obtained from various and complex analyses of narrow cuts (Waterman method), correlations have been found f ctween refractive index, specific gravity and molecular weight on one hand, and percentages of paraffinic, naphthenic and aromatic carbon on the other. 

In addition to the numeric data (color, solubility, refraction index, spectra, etc.), these factual databases also include a bibliographic section with references or sources and a section with information for the identification of a compound (e.g., name, CAS Registry Number, molecular weight). 

Interpret the slope and intercept values of the line in Fig. 10.12 in terms of the molecular weight and radius of gyration of cellulose nitrate in this solution. At 436 nm the refractive index of acetone is 1.359. 

Using the original Hc2/r values, recalculate M using the various refractive index gradients. On the basis of self-consistency, estimate the molecular weight of this polymer and select the best value of dn/dc2 in each solvent. Criticize or defend the following proposition Since the extension of the Debye theory to large particles requires that the difference between n for solute and solvent be small, this difference should routinely be minimized for best results. 

Solution Polymers. Acryflc solution polymers are usually characterized by their composition, solids content, viscosity, molecular weight, glass-transition temperature, and solvent. The compositions of acryflc polymers are most readily determined by physicochemical methods such as spectroscopy, pyrolytic gas—liquid chromatography, and refractive index measurements (97,158). The solids content of acryflc polymers is determined by dilution followed by solvent evaporation to constant weight. Viscosities are most conveniently determined with a Brookfield viscometer, molecular weight by intrinsic viscosity (158), and glass-transition temperature by calorimetry. 

PFC number Formula CAS Registry Number Molecular weight Boiling point, °C Melting point, °C Liquid density, g/mL at °C Liquid refractive index, at°C Critical temp, °C Critical pressure, MPa "... 

Formula GAS Registry Number Molecular weight Boiling poiut, °G Melting poiut, °G Liquid density, g/mL at °G Refractive index, n- at °G... 

Compound CAS Registry Number Molecular weight Melting point, °C Boiling point, °C" Refractive index Specific gravity Viscosity mPa(=cP) Solubihty in water at 25°C F poi... 

In methacrylic ester polymers, the glass-transition temperature, is influenced primarily by the nature of the alcohol group as can be seen in Table 1. Below the the polymers are hard, brittle, and glass-like above the they are relatively soft, flexible, and mbbery. At even higher temperatures, depending on molecular weight, they flow and are tacky. Table 1 also contains typical values for the density, solubiHty parameter, and refractive index for various methacrylic homopolymers. 

Hplc techniques are used to routinely separate and quantify less volatile compounds. The hplc columns used to affect this separation are selected based on the constituents of interest. They are typically reverse phase or anion exchange in nature. The constituents routinely assayed in this type of analysis are those high in molecular weight or low in volatility. Specific compounds of interest include wood sugars, vanillin, and tannin complexes. The most common types of hplc detectors employed in the analysis of distilled spirits are the refractive index detector and the ultraviolet detector. Additionally, the recent introduction of the photodiode array detector is making a significant impact in the analysis of distilled spirits. 

Melting points, boiling points, densities, and refractive indexes for carboxyUc acids vary widely depending on molecular weight, stmcture, and the presence of unsaturation or other functional groups (Tables 1,2,3, and 5). In addition, some useful constants for alkanoic acids are Hsted in Table 1. Some constants for selected unsaturated and substituted acids are given in Table 7. 

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