What is the purpose of blank solution in spectrophotometry?

The blank solution consists of the solvent used to dissolve the specimen. Because other compounds in a solution (or the solvent itself) may absorb the same wavelengths as the compound being yzed, we compare the absorbance of the test solution to a reference blank. Ideally, the reference blank should contain everything found in the sample solution except the substance you are trying to yze or measure.