Introduction & Background:
The purpose of this lab was to determine the concentration of a sodium hydroxide solution by titrating it with a standard solution of known concentration. Titration is used to determine the quantity of one reactant when another is known. The equivalence point tells the volume of the unknown reactant needed for the two solutions to react in a stoichiometric ratio. A pH sensor is used to detect the equivalence point. The volume of the unknown solution during the equivalence point, along with the number of moles in the unknown solution, can be used to determine the concentration of the unknown solution.
NaOH is the solution with the unknown concentration in this lab. NaOH with titrated with the known concentration and moles solution KHP, to find the concentration of NaOH. NaOH readily absorbs moisture from the air, therefore the mass does not provide precise information about the amount of NaOH present in the sample. A Titrator pump, along with a data collection system is used by finding the equivalence point. The equivalence point is shown on the graph when there is a large jump in the pH, then the line flattens out again.