In the presence of hydroxide ions the organic crystal violet pigment is chemically converted to a colorless compound. This conversion is colorimetric in nature and is slow enough that a colorimeter of spectrophotometer can measure the absorbance of the crystal violet solution and track the kinetics of the reaction.

In this experiment, you will observe the reaction between crystal violet and sodium hydroxide. In addition, the rate coefficient for crystal violet will be determined and a pseudo-rate law will be constructed.