Expansion in volume

When most of the alcohol has distilled, a yellow scum forms on the surface of the red, viscous liquid. The distillation is stopped at this point. When the solution is cooled, the sodium derivative crystallizes with considerable expansion in volume. 

STEAM EXPLOSION Ovetpressure associated with the rapid expansion in volume on instantaneous conversion of water to steam. 

The phase change of a chemical from solid to liquid generally results in an expansion in volume. (Ice to water is one exception.) As a result ... 

The eoneentration of ozone in O2/O3 mixtures ean be determined by eatalytie deeomposition to O2 in the gas phase and measurement of the expansion in volume. More eonveniently it ean be determined iodometrieally by passing the gas mixture into an alkaline borie-aeid-buffered aqueous solution of KI and determining the I2 so formed by titration with sodium thiosulfate in aeidified solution ... 

M FIGURE 8.4 The expansion in volume that occurs during a reaction forces the piston outward against atmospheric pressure P. The amount of work done is equal to the pressure exerted in moving the piston (the opposite of atmospheric pressure, — P) times the volume change (AV). The volume change is equal to the area of the piston (A) times the distance the piston moves (d). Thus, w = —PAV. 

Solutions of alkali metals in liquid ammonia at all concentrations, with the exception of cesium, are less dense than either of the constituents. This behavior for metal ammonia solutions is unique in that the expansion in volume is much larger than that shown on forming solutions of normal electrolytes or non-electrolytes. 

Now that you ve finished practising Boyles law problems, take a deep breath and relax. You have just illustrated Boyles law When you inhale, muscles in your torso expand your rib cage. The volume of your lungs increases. Since the pressure inside your lungs is decreased with the expansion in volume, outside air under higher pressure rushes in. 

If the expansion in volume is dV, the distance the piston moves is dx and the area of the piston is A, then... 

Cationic polymerization of spiroorthoesters is of interest because, in contrast to the vast majority of polymerization processes, conversion of spiro monomer into linear polymer is accompanied by expansion in volume. In the first report on the cationic polymerization of 1,4,6-trioxaspiro[4.4]-nonane ... 

Figure 9.1 Expansions in volume of solvents (a) acetonitrile and (b) acetone in the presence of carbon dioxide at varying pressures, 1 MPa = 1 bar. [Reprinted with permission from J. Phys. Chem. B, 2006, 110, 13195-13202. Copyright 2006 American Chemical Society.]...

Overflow theory The overflow theory (F. L. Liebermann et al., 1970) (7) is based on the principle that retention of sodium already exists as a primary event and hence causes an expansion in volume. 

Bailey continues his series of papers in the area of ringopening polymerization with expansion in volume (109. 110). 

Cationic Ring-Opening Polymerization with Expansion in Volume... 

The polymerization is accompanied by approximately 6% shrinkage (calculated from densities of monomer and polymer at 25 °C). Upon heating the polymer solution in the presence of trifluoromethanesulfonic acid the substituted 1,3-dioxolane ring opens and linear polymer is formed. This is accompanied by a 9.7% expansion in volume. 

According to these results expansion in volume during polymerization occurs only when both fused rings open upon polymerization. 

Several other treatments of solvent effects on solvolysis rates have been developed. The equations typically include several terms related to (a) macroscopic nonspecific solvent properties, such as the dipole moment and dielectric constant (b) empirical polarity criteria, such as Ej.(30) (c) solvent electrophilicity and nucle-ophilicity parameters and (d) terms related to solvent cohesivily. The last term accounts for the difference in work required to disrupt structure within the solvent, when, for example, there is expansion in volume between reactants and the TS. 

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