- Quantitative analysis

- Qualitative analysis, especially of organic compounds

- Fundamental studies of the electronic structure of atomic and molecular species

- Quantitative determination of the principal and trace constituents in metals and alloys

- Quantitative determination of trace constituents in environmental (air and water) samples. These determinations are often conducted on-site

- Measurement of the rates of chemical reactions

- Identification of the functional groups in organic molecules

- Detection of species in the effluent of liquid chromatographs

- On-line monitoring of species in process streams

- Quantitative analysis of electroplating and chemical treatment baths

- Analysis of wastewater streams before and after treatment

- Form: Gas, liquid, or solid. Analyses are most commonly performed on liquid solutions

- Size: For solutions, typical sample volumes range from approximately 0.1 to 30 mL

- Preparation: Often quite complex. Complexity increases with the difficulty of placing the analyte in solution and the number of interferences

- For quantitative analysis of inorganic ions, spectroscopic samples may contain as little as 0.01 mg/L in the case of species that form highly absorbing complexes

- For qualitative analysis of organic compounds, concentrations of spectroscopic samples may be as small as 100 nanomolar

- The initial capital outlay for ultraviolet/visible spectrophotometric techniques is usually far less than that for related techniques

- The analyte must absorb radiation from 200 to 800 nm, or be capable of being converted into a species that can absorb radiation in this region

- Additional steps are often necessary to eliminate or account for interferences by species (other than the analyte) that also absorb radiation near the analytical wavelength

- The actual time required to analyze each sample is a matter of minutes. However, it may take several hours to prepare the sample, make the standards, and create a calibration curve

- Molecular fluorescence spectroscopy: For molecules that fluoresce strongly, this technique offers significantly greater sensitivities and freedom from interferences

- Atomic absorption spectroscopy, optical emission spectroscopy: For quantitative analysis of metals and some nonmetals, these techniques usually offer better sensitivity and almost complete freedom from interferences