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,...
For example, assuming a resting membrane potential of –80 mV for a cardiac cell, a calculation in accord to the Nernst equation gives an intracellular pH of 6.1 for a cell that would be bathed in an extracellular medium of pH 7.4. A pHi of 6.1 would be incompatible with cellular ...
Classical pH sensors are based on the equilibrium between two forms (protonated and nonprotonated) and are restricted by the Henderson-Hasselbalch equation; thus, the transition width of these sensors covers 2 pH units (pKa ± 1 pH unit). The development of highly responsive i-motif-based pH ...
The equation of interest is known as the Henderson-Hasselbach equation and is written: \(pH = pKa + log_{10}\dfrac{[A^{-}]}{[HA]}\) This means that given an acid's pKa and the relative concentration of anion and "intact" acid, you can determine the pH. Ka values can be easily...
One useful derived equation (valid in a solution where part of the sample precipitates early in the titration) is:log So = log (C/2) - |pKa|where C is the sample concentration, So is the intrinsic solubility of the unchanged substance, and pKa = pKappa - pKa, the difference between ...
根据亨德森-哈塞尔巴尔赫方程(Henderson-Hasselbalch Equation) 对于酸:pH = pKa + log [A-] / [HA] 对于碱:pH = pKa + log [B] / [BH+] 溶液pH值、可提取物的酸离解常数(pKa)、其在特定pH值下的有效溶解度(Se)及其固有溶解度(S0)之间的关系表示如下 对于酸:pH=pKa+log(S-S0)/(S0),即 log ...
with the acid ionization constant: Ka=[A−][H+]/[HA]Ka=[A−][H+]/[HA] A similar chemical reaction between base BOH and water looks like this: BOH⇌OH−+B+BOH⇌OH−+B+ The next equation gives the base ionization constant for the above formula: Kb=[OH−][B+]/[BOH]...
(Φan = 1) by the respective fractions. TheΦnandΦanterms are the fractions of neutral and anionic forms of a monovalent acidic herbicide, that have been calculated as a function ofpKaand the actual pH in the soil suspension with the use of the modified Henderson–Hasselbalch equation:...
3.1. Estimation of pKa values Estimated pKas can be found in Table 1, along with a comparison to reference pKa values from model amino acid compounds [49]. All pKa values were fit to a Henderson-Hasselbalch equation with a Hill modification; correlation coefficients for all estimated pKas are...
It's worth noting that sometimes this equation is written for the Kavalue rather than pKa, so you should know the relationship: pKa = -logKa Assumptions for the Henderson-Hasselbalch Equation The reason the Henderson-Hasselbalch equation is an approximation is because it takes water chemistry out...