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The equilibrium constant of the acid-alcohol based polyesterification is typically K C ≤ 10, what is not high enough to obtain high-molecular weight polymers (DP n ≥ 100), as the number average degree of polymerization (DP n) can be calculated from the equilibrium constant K C. [20] = +
The thermodynamic description of contact angles of a drop of liquid on a solid surface are derived from the equilibrium formed between the chemical potentials of the solid–liquid, solid–vapor, and liquid–vapor interfaces. A contact angle of a liquid sample. At equilibrium, the contact angle of a liquid drop on a surface does not change.
The equilibrium constant of a chemical reaction is the value of its reaction quotient at chemical equilibrium, a state approached by a dynamic chemical system after sufficient time has elapsed at which its composition has no measurable tendency towards further change. For a given set of reaction conditions, the equilibrium constant is ...
Chemical potentials are important in many aspects of multi-phase equilibrium chemistry, including melting, boiling, evaporation, solubility, osmosis, partition coefficient, liquid-liquid extraction and chromatography. In each case the chemical potential of a given species at equilibrium is the same in all phases of the system. [6]
The most basic approach is to manipulate the various equilibrium constants until the desired concentrations are expressed in terms of measured equilibrium constants (equivalent to measuring chemical potentials) and initial conditions. Minimize the Gibbs energy of the system. [20] [21] Satisfy the equation of mass balance.
Chemical equilibrium is a dynamic state in which forward and backward reactions proceed at such rates that the macroscopic composition of the mixture is constant. Thus, equilibrium sign ⇌ symbolizes the fact that reactions occur in both forward ⇀ {\displaystyle \rightharpoonup } and backward ↽ {\displaystyle \leftharpoondown } directions.
The Van 't Hoff equation relates the change in the equilibrium constant, K eq, of a chemical reaction to the change in temperature, T, given the standard enthalpy change, Δ r H ⊖, for the process. The subscript r {\displaystyle r} means "reaction" and the superscript ⊖ {\displaystyle \ominus } means "standard".
When an equilibrium constant K is expressed as a concentration quotient, = [] [] [] [] it is implied that the activity quotient is constant. For this assumption to be valid, equilibrium constants must be determined in a medium of relatively high ionic strength. Where this is not possible, consideration should be given to possible activity ...