最早,劳伦斯·约瑟夫·亨德森在研究碳酸的缓冲能力时提出亨德森方程,后来,卡尔·阿尔伯特·哈塞尔巴尔赫将亨德森方程写为对数形式,并用于研究血液中碳酸引起的代谢性酸中毒(拓展阅读:Henderson-Hasselbalch equation and the pH of buffer solution)。
1. The relationship between pH and pKa is expressed by the formula: pH = pKa + log([A-]/[HA]).2. This equation indicates that a lower pKa value signifies a more acidic substance.3. Conversely, a higher pKa value indicates a weaker acidity in the substance.4. Consequently,...
Relating pH and pKa With the Henderson-Hasselbalch Equation If you know either pH or pKa, you can solve for the other value using an approximation called theHenderson-Hasselbalch equation: pH = pKa + log ([conjugate base]/[weak acid]) pH = pka+log ([A-]/[HA]) pH is the sum of th...
When pKa is higher than pH? The pKa is higher than the pH if there is more of the basic form in a solution than the acidic form. This comes from the Henderson-Hasselbalch equation. What is the relation between pH and pKa? pH and pKa are related through the Henderson-Hasselbalch equation...
Four methods—two graphical and two mathematical— were used to estimate the acid dissociation constant (pKa) and isosbestic point using absorbance measurements. The equation for the dependence of the absorbance on pH at λ = 600 nm was obtained using calibration curves. The resulting average pKa ...
The pKavalues for –COOH groups in M and G are 3.38 and 3.65, respectively. This results in precipitation of the soluble polymer below pH 2. However, most of the applications of alginate arise from the fact that it forms insoluble gels/precipitates withdivalentmetal ions, especially Ca2+. Th...
pH = pKa+ log10([A-]/[AH]) Where the square brackets are used to indicate the concentrations of the acid and its conjugate base. The equation may be rewritten as: Ka/[H+] = [A-]/[AH] This shows that pKa and pH are equal when half of the acid has dissociated. The buffering ...
One useful derived equation (valid in a solution where part of the sample precipitates early in the titration) is: log So = log (C/2) - |螖pKa| where C is the sample concentration, So is the intrinsic solubility of the unchanged substance, and 螖pKa = pKappa - pKa, the difference ...
The pH value where the titratable group is half-protonated is equal to the pKa if the titration curve follows theHenderson-Hasselbalch equation. Most pKa calculation methods silently assume that all titration curves are Henderson-Hasselbalch shaped, and pKa values in pKa calculation programs are there...
The Statistical Assessment of Modeling of Proteins and Ligands (SAMPL) challenges focuses the computational modeling community on areas in need of improvem