Abstract: acid-base titration is a technique commonly used to determine the moles of acid in a sample by adding a known volume of strong base of a known concentration. The strong base provides the hydroxide ion, to react quantitatively with the acid. The point at which the acid is completely and exactly consumed the known quantity of base is called the equivalence end point and is signalled by a colour change in the solution (end point). This colour change is created by an indicator dye which is extremely sensitive to the presence of even a small excess of aqueous. From the stoichiometry of the balanced chemical reaction, the number of moles of the unknown acid solution can be determined. If the number of grams unknown acid is measured, the molecular weight can be calculated. Titration is the process of the gradual addition of a standard solution to a second solution until all of the solute in the second solution has completely reacted.
Introduction: in the experiment you will be determining the molarity of an unknown acid solution by measuring the volume of a sodium hydroxide solution of known concentration required to neutralize a measured volume of the unknown acid solution. The indicator is added because there is no observation change that occurs when the neutralization reaction is complete. The indicator used in this experiment, phenolphthalein, is colourless in acidic solution but turns pink when there is an excess of base present, therefore you will know when the reaction is complete when you see the first faint of pink colour in the reaction mixture. Because the pink colour occurs when there is an excess of base present, the lighter the pink colours is at the end the better.
Safety; when handling acids, bases and chemical indicators, wear safety glasses. The skin should be immediately washed with water for several minutes if exposed to any chemical. During the titration maintain