Entropy increase associated with decrease

The observation that IfH(en) > Kh(NH3) is qualitatively supported by the enthalpy and entropy changes associated with the first acid dissociation equilibrium (Table XXII). Increased hydrogen bond stabilization should contribute negatively to both AH°(Kal) and AS°(Kal), which is consistent with the observation for both chromium(III) and rhodium(III) that it is the ammine complexes which have the highest AH°(Kal) and AS°(Kal) values. The greater acid strength of the ethylenediamine systems is then due to a decrease of AH0, which is greater than the decrease of AS0. The AH°(Kai) and param-... 

Increase in entropy is associated with (i) decrease in order, (ii) increase in disorder and (iii) loss of information as predicted by Statistical Mechanics. Everything tends towards disorder. Any process that converts from one energy to another must lose heat. The universe is one-way street. Entropy must always increase in the universe and in any hypothetical system, within it. Although d S is greater than zero d S can be less than zero under certain circumstances, thereby generating a particular type of ordered structure which is called dissipative structure. 

In the dissolving of ammonium nitrate in water, for example, a crystalline solid and a pure liquid are replaced by a mixture of ions and water molecules in the liquid (solution) state. This situation is somewhat more involved than the first two because some decrease in entropy is associated with the clustering of water molecules around the ions because of ion-dipole forces. The increase in entropy that accompanies the destruction of the solid s crystalline lattice predominates, however, and for the overall dissolution process, AS > 0. 

It has been seen in deriving equations 4.33 to 4.38 that for a small disturbance the velocity of propagation of the pressure wave is equal to the velocity of sound. If the changes are much larger and the process is not isentropic, the wave developed is known as a shock wave, and the velocity may be much greater than the velocity of sound. Material and momentum balances must be maintained and the appropriate equation of state for the fluid must be followed. Furthermore, any change which takes place must be associated with an increase, never a decrease, in entropy. For an ideal gas in a uniform pipe under adiabatic conditions a material balance gives ... 

Microdomain stmcture is a consequence of microphase separation. It is associated with processability and performance of block copolymer as TPE, pressure sensitive adhesive, etc. The size of the domain decreases as temperature increases [184,185]. At processing temperature they are in a disordered state, melt viscosity becomes low with great advantage in processability. At service temperamre, they are in ordered state and the dispersed domain of plastic blocks acts as reinforcing filler for the matrix polymer [186]. This transition is a thermodynamic transition and is controlled by counterbalanced physical factors, e.g., energetics and entropy. 

Papisov et al. (1974) performed calorimetric and potentiometric experiments to determine the thermodynamic parameters of the complex formation of PMAA and PAA with PEG. They investigated how temperature and the nature of the solvent affected the complex stability. They found that in aqueous media the enthalpy and entropy associated with the formation of the PMAA/PEG complex are positive while in an aqueous mixture of methanol both of the thermodynamic quantities become negative. The exact values are shown in Table II. The viscosities of aqueous solutions containing complexes of PMAA and PEG increase with decreasing temperature as a result of a breakdown of the complexes. 

In most solids vibrations parallel to bond directions decrease in frequency as the volume increases and the entropy (eq. (11.14)) increases with volume (dS/dV)T and the thermal expansion are positive. Negative thermal expansion is usually associated with more open structures where coordination numbers are low and vibrations perpendicular to bond directions can dominate the change in entropy with volume and thus the derivative (dS/dV)T. 

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