Homogenizing mixtures

For methyl alcohol, two volumes of synthetic n-hexane, b.p. 68-6-69 0° (uncorr.), and one volume of the alcohol to be tested are mixed and the homogeneous mixture is cooled in ice until the appearance of a cloudiness. A thermometer is placed in the solution, which is allowed to warm gradually to the temperature at which the second phase disappears. The... 

Illustration showing separation by equilibrium-density-gradient centrifugation. The homogeneous mixture in (a) separates into three bands (b) after applying centrifugal force. 

In the calciaation process, a mixture of corresponding oxides and an optional modifier, eg, molybdic acid, are milled together to achieve a homogenous mixture. The mixture is calciaed at 750—950°C and milled to a desired particle size. Wet milling ia an alkaline medium is recommended to remove any unreacted vanadium salts that ate beheved to degrade the pigmentary properties of bismuth vanadate (39). 

Potassium chloride coUectors are primary amines derived from beef taUow. Commercially available amine is a homogeneous mixture of palmityl-. 

Allophane and Imogolite. AUophane is an amorphous clay that is essentially an amorphous soHd solution of sUica, alumina, and water (82). In allophane less than one-half of the aluminum is held in tetrahedral coordinations and the Si02 to AI2O2 ratio typically varies between 1.3 and 2.0, but values as low as 0.83 have been reported. The typical morphology of allophane is cylindrical (37). AUophane may be associated with haUoysite, smectite minerals, or it may occur as a homogeneous mixture with evansite, an amorphous soHd solution of phosphoms, alumina, and water. Its composition, hydration, and properties vary. Chemical analyses of two allophane samples are given in Table 5. 

One particular case of multicomponent diffusion that has been examined is the dilute diffusion of a solute in a homogeneous mixture (e.g., of A in B -h C). Umesi and Danner compared the three equations given below for 49 ternaiy systems. All three equations were equivalent, giving average absolute deviations of 25 percent. 

Elammability Limits The minimum and maximum concentrations of combustible material in a homogeneous mixture with gaseous oxidizer that will propagate a flame. 

Preparation (i) (ii) Remove the skin from the surface of the primer, if any. and stir well the contents of the drum to make it a homogenous mixture Filler the mixture through a cambric cloth ... 

As applied to vinyl dispersions, the heating of a dispersion, forming a homogeneous mixture. Fluxing temperature temperature at which fusion occurs in vinyl dispersions. 

An important purpose of agitation or mixing is to bring a number of materials together in a physically homogeneous mixture. Two or more fluids are either blended or dispersed as emulsions fluids and finely divided solids are dispersed as suspensions, gases dispersed as fluids, or soluble substances dissolved. Mixing of process fluids is reviewed in Chapter 7. 

The singlet equations, PYl and HNCl, ean alternatively be derived [24,50] by eonsidering a homogeneous mixture of A - - 1 eomponents... 

Where, 5 is defined as the solubility parameter of the solvent. So, 8p and 8h are the dispersion, polar, and H-bonding forces, respectively. A homogenous mixture of polar solvents can also be used as the continuous phase. In this case, the solubility parameter of the homogeneous mixture is calculated according to the following expression [89] ... 

When temperature is constant and at equilibrium for a homogeneous mixture (such as azeotrope), the composition of the liquid is identical with the composition of the vapor, thus xj = y, and the relative volatility is equal to 1.0. 

The average molecular weight (M) of a homogeneous mixture is its total mass (m) divided by the total number of moles (n) of its components. If x. represents the mole fraction of the i component whose molecular weight is M, then... 

The mass concentration (p.) of the i component (or species) in a homogeneous mixture is defined as the mass of that component present per unit volume of the... 

Two mixtures. On the left is brass, a homogeneous mixture of copper and zinc. On the right is a piece of granite, a heterogeneous mixture that contains discrete regions of different minerals (feldspar, mica, and quartz). 

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