One example of a primary standard in titration is potassium hydrogen phthalate (KHP). KHP is a solid compound that can be easily weighed and dissolved in water to prepare a standard solution. It is used as a primary standard because it is stable, has a high purity, and can be accurately weighed. KHP reacts with a strong base, such as sodium hydroxide (NaOH), in a 1:1 stoichiometric ratio, making it suitable for titrations. The reaction between KHP and NaOH can be represented by the balanced equation: