Equilibrium constant in terms of concentrations

The solubility of a compound refers to the concentration of that compound in solution, either as a molarity or as a mass per unit volume. The solubility product constant is the equilibrium constant in terms of concentrations of ions, for the dissolution equilibrium, raised to their appropriate coefficients. 

Because the concentration of CO is not negligible, we can no longer apply the simple relationship between molality and concentration (mi = cjp) to write the equilibrium constant in terms of concentrations. The correct relationship between these two quantities is now given by equation 14.23, where M and n are the molar mass and the amount of substance of the solvent, respectively, and M and , are the corresponding quantities for the three solutes. 

Since kj and k, are constants a new constant can be derived from them. It is named as an equilibrium constant in terms of concentration, and is symbolized as K, . 

The equilibrium constant of the above reaction in terms of partial pressures (Kp) is 6 at 167 °C. What is the equilibrium constant in terms of concentration (K ) ... 

The equilibrium constant in terms of concentrations can be calculated from... 

Equilibrium Constant for Weak Electrolyte. Knowing the concentration c of the weak electrolyte, say HAc, and its degree of ionization a at that concentration, the concentrations of H and Ac ions and of un-ionized HAc can be calcnlated. Then the equilibrium constant in terms of concentrations can be calculated from... 

We call Kc the equilibrium constant in terms of concentrations. We use the term constant here with some reservation quilibrium constants are highly dependent on the temperature, sometimes increasing with temperature and sometimes decreasing, depending on the particular reaction. 

It can also be shown that Kct the equilibrium constant in terms of concentrations, is related to the partition functions evaluated per unit volume... 

Both the symbols K and are used commonly for an equilibrium constant in terms of concentrations. We will always use K in this book. The symbol Kp represents an equilibrium constant in terms of partial pressures. 

Equilibrium constant in terms of concentrations, (mol/m ) + +- A- v Ionization constants of a given acid in water and alcohol. 

Even very small solubility products can be measured electrically, and these values are listed in chemical tables. As the above exercise illustrates, the solubility of a substance can be derived from its solubility product. Solubility products are generally listed only for slightly or sparingly soluble substances. If is very small, the substance is often termed insoluble (in water). In the case of moderately and highly soluble substances (such as NaCl or NaOH), the use of solubility products is not very useful. This is because instead of defining an equilibrium constant in terms of concentrations we would have to... 

The principles of microscopic reversibility and detailed balancing imply a fundamental relationship (see Table V) between the equilibrium constant (in terms of concentrations) and the rate constants of the reversible processes. Of course, two relations are obtained, one between entropies, and one between enthalpies. 

Equilibrium constants in terms of concentrations, K, ar d partial pressure, Kp, can be deduced from appropriate data. 

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