Introduction & Background:

The purpose of this lab is to determine the molar concentration of a strong acid solution by titrating measured volumes with a strong base of known concentration. Titration is a common laboratory method that is used to determine the concentration of a reactant. The stoichiometric ratios between the solutions reacts during titration and the equivalence point can be determined.  The equivalence point is shown as a large jump in the pH on the graph.

The titrant in this experiment is NaOH, and the reactant is HCl. The concentration of NaOH was determined in the previous lab, 6a.  The NaOH is a strong base, and the HCl is a strong acid.  The product of the acid-base reaction is always water.  This type of reaction is known as a neutralization reaction.  When the NaOH is titrated with HCl, the volume of NaOH needed to react with HCl in a stoichiometric ratio can be found. The volume and concentration of NaOH is used to determine the number of moles of NaOH needed during the titration.  The stoichiometric ratio between NaOH and HCl is a 1:1 ratio, so the moles of NaOH and HCl is the same.  The moles of HCl and volume of HCl ( 20.00mL in this lab) can be used to determine the concentration of HCl.