Titration of Hydrochloric Acid

A graphic picture of what happens during an acid-base titration is easily produced in the laboratory. Consider again what is happening as a titration proceeds. Consider, specifically, NaOH as the titrant and HCI as the substance titrated. In the titration flask, the following reaction occurs when titrant is added  

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Swim, J. Earps, E. Reed, L. M. et al. Gonstant-Gurrent Goulometric Titration of Hydrochloric Acid, /. Chem. Educ. 1996, 73, 679-683. 

On p. 124 you saw that it was possible to prepare a soluble salt by reacting an acid with a soluble base (alkali). The method used was that of titration. Titration can also be used to find the concentration of the alkali used. In the laboratory, the titration of hydrochloric acid with sodium hydroxide is carried out in the following way. 

One of the most common titrations of this type is the titration of hydrochloric acid, HC1, with sodium hydroxide, NaOH. If you remember from earlier, this is a neutralization reaction. However, you should also remember from earlier that in order for a complete neutralization to occur, the reaction must use appropriate stoichiometric ratios. When we first look at the process, we will do so with two solutions of known concentration, but you will see that this process can be used to determine the concentration of one of the solutions. 

Consider an analytical method involving the titration of hydrochloric acid with anhydrous sodium carbonate to determine the concentration of the acid. The measurements made are mass (weighing out a chemical to make up a solution of known concentration) and volume (dispensing liquids with pipettes and burettes). The reaction between the two chemicals is based on amount of substance - one mole of sodium carbonate reacts with two moles of hydrochloric acid - and the mass of a mole is known (e.g. the formula weight in grams of one mole of sodium carbonate is 105.99). All the measurements are based on either length or mass and are traceable to SI units, so the method is a primary method. 

The titration of an acid solution with a standard solution of alkali will determine the amount of alkali which is equivalent to the amount of acid present (or vice versa). The point at which this occurs is called the equivalence point or end-point. For example, the titration of hydrochloric acid with sodium hydroxide can be expressed as follows ... 

Fig. 7.15 Diagrams of conductivity titrations of hydrochloric acid and acetic acid [15]...

Fig. 3. The Titration of Hydrochloric Acid with 0.1010 Normal Sodium Hydroxide.

In the case of a strong acid versus a strong base, both the titrant and the analyte are completely ionized. An example is the titration of hydrochloric acid with sodium hydroxide ... 

Titration of hydrochloric acid with sodium silicate (silica sol formed)... 

Titration of hydrochloric acid, containing a small amount of aluminum chloride, with sodium hydroxide (aluminum hydroxide precipitated)... 

Titration of Hydrochloric Acid of Various Concentrations with Sodium... 

A) titration of hydrochloric acid with sodium hydroxide (type... 

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