Search results
Results from the WOW.Com Content Network
For a strong acid-strong base titration monitored by pH, we have at any i'th point in the titration = [+] [] where K w is the water autoprotolysis constant.. If titrating an acid of initial volume and concentration [+] with base of concentration [], then at any i'th point in the titration with titrant volume ,
The equivalence point, or stoichiometric point, of a chemical reaction is the point at which chemically equivalent quantities of reactants have been mixed. For an acid-base reaction the equivalence point is where the moles of acid and the moles of base would neutralize each other according to the chemical reaction.
Note that when an acid neutralizes a base, the pH may or may not be neutral (pH = 7). The pH depends on the strengths of the acid and base. In the case of a weak acid and strong base titration, the pH is greater than 7 at the equivalence point. Thus pH can be calculated using the following formula: [1]
A typical titration curve of a diprotic acid, oxalic acid, titrated with a strong base, sodium hydroxide.Both equivalence points are visible. Titrations are often recorded on graphs called titration curves, which generally contain the volume of the titrant as the independent variable and the pH of the solution as the dependent variable (because it changes depending on the composition of the ...
The pH at the end-point depends mainly on the strength of the acid, pK a. The pH at the end-point is greater than 7 and increases with increasing concentration of the acid, T A, as seen in the figure. In a titration of a weak acid with a strong base the pH rises more steeply as the end-point is approached. At the end-point, the slope of the ...
Normality can be used for acid-base titrations. For example, sulfuric acid (H 2 SO 4) is a diprotic acid. Since only 0.5 mol of H 2 SO 4 are needed to neutralize 1 mol of OH −, the equivalence factor is: f eq (H 2 SO 4) = 0.5. If the concentration of a sulfuric acid solution is c(H 2 SO 4) = 1 mol/L, then its normality is 2 N. It can also be ...
Likewise, any aqueous base with an association constant pK b less than about 0, corresponding to pK a greater than about 14, is leveled to OH − and is considered a strong base. [22] Nitric acid, with a pK value of around −1.7, behaves as a strong acid in aqueous solutions with a pH greater than 1. [23] At lower pH values it behaves as a ...
In acid-base titrations, an unfitting pH indicator may induce a color change in the indicator-containing solution before or after the actual equivalence point. As a result, different equivalence points for a solution can be concluded based on the pH indicator used. This is because the slightest color change of the indicator-containing solution ...