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In thermodynamics, the ebullioscopic constant K b relates molality b to boiling point elevation. [1] It is the ratio of the latter to the former: = i is the van 't Hoff factor, the number of particles the solute splits into or forms when dissolved. b is the molality of the solution.
K b, the ebullioscopic constant, which is dependent on the properties of the solvent. It can be calculated as K b = RT b 2 M/ΔH v, where R is the gas constant, and T b is the boiling temperature of the pure solvent [in K], M is the molar mass of the solvent, and ΔH v is the heat of vaporization per mole of the solvent.
A smaller H + concentration means a greater OH − concentration and, therefore, a greater K b and a greater pH. NaOH (s) (sodium hydroxide) is a stronger base than (CH 3 CH 2) 2 NH (l) (diethylamine) which is a stronger base than NH 3 (g) (ammonia). As the bases get weaker, the smaller the K b values become. [1]
In chemistry and biochemistry, the Henderson–Hasselbalch equation = + ([] []) relates the pH of a chemical solution of a weak acid to the numerical value of the acid dissociation constant, K a, of acid and the ratio of the concentrations, [] [] of the acid and its conjugate base in an equilibrium.
The Gran plot is based on the Nernst equation which can be written as = + {+} where E is a measured electrode potential, E 0 is a standard electrode potential, s is the slope, ideally equal to RT/nF, and {H +} is the activity of the hydrogen ion.
The K b values for dissociation of spermine protonated at one or other of the sites are examples of micro-constants. They cannot be determined directly by means of pH, absorbance, fluorescence or NMR measurements; a measured K b value is the sum of the K values for the micro-reactions.
This method was first developed by Benesi and Hildebrand in 1949, [2] as a means to explain a phenomenon where iodine changes color in various aromatic solvents. This was attributed to the formation of an iodine-solvent complex through acid-base interactions, leading to the observed shifts in the absorption spectrum.
The number ratio can be related to the various units for concentration of a solution such as molarity, molality, normality (chemistry), etc. The assumption that solution properties are independent of nature of solute particles is exact only for ideal solutions , which are solutions that exhibit thermodynamic properties analogous to those of an ...