Search results
Results From The WOW.Com Content Network
The Henderson–Hasselbalch equation can be used to estimate the pH of a buffer solution by approximating the actual concentration ratio as the ratio of the analytical concentrations of the acid and of a salt, MA. The equation can also be applied to bases by specifying the protonated form of the base as the acid.
As calculated by the Henderson–Hasselbalch equation, in order to maintain a normal pH of 7.4 in the blood (whereby the pK a of carbonic acid is 6.1 at physiological temperature), a 20:1 ratio of bicarbonate to carbonic acid must constantly be maintained; this homeostasis is mainly mediated by pH sensors in the medulla oblongata of the brain ...
The ratio of acid, AH and conjugate base, A −, concentrations varies as the difference between the pH and the pK a varies, in accordance with the Henderson-Hasselbalch equation. The pH of a solution of a monoprotic weak acid can be expressed in terms of the extent of dissociation.
The ratio of concentration of conjugate acid/base to concentration of the acidic/basic indicator determines the pH (or pOH) of the solution and connects the color to the pH (or pOH) value. For pH indicators that are weak electrolytes, the Henderson–Hasselbalch equation can be written as: pH = pK a + log 10 [Ind −] / [HInd]
This is the Henderson–Hasselbalch equation, from which the following conclusions can be drawn. At half-neutralization the ratio [A −] / [HA] = 1; since log(1) = 0, the pH at half-neutralization is numerically equal to pK a. Conversely, when pH = pK a, the concentration of HA is equal to the concentration of A −.
Hence, the pK of each buffer will dictate the ratio of the concentrations of its base and weak acid forms at the given pH, in accordance with the Henderson-Hasselbalch equation. Any condition that changes the balance of one of the buffer systems, also changes the balance of all the others because the buffer systems actually buffer one another ...
In this case H 0 and H − are equivalent to pH values determined by the buffer equation or Henderson-Hasselbalch equation. However, an H 0 value of −21 (a 25% solution of SbF 5 in HSO 3 F) [5] does not imply a hydrogen ion concentration of 10 21 mol/dm 3: such a "solution" would have a density more than a hundred times greater than a neutron ...
He wrote the Henderson equation in 1908 to describe the use of carbonic acid as a buffer solution. Karl Albert Hasselbalch later expressed the equation in logarithmic terms, creating the Henderson–Hasselbalch equation. [3] In addition, he described blood gas transport and the general physiology of blood as physico-chemical system (1920–1932).