Instrumental analysis plays an important role for forensic science practitioners in many areas, including but not limited to, trace evidence, fire and arson investigation, toxicology, and controlled substances. A physical property of the sample to be analyzed is chosen in instrumental analysis for the determination of its chemical composition. Analysis of the sample can be of any type i.e. biochemical, organic, inorganic, physical, or analytical. Irrespective of the type of analysis, the main purpose to be served is to extract information about the composition of the sample. This is the reason why instrumental analysis is also known as quantitative analysis. The type of instrumental technique used depends on the property of the sample measured.