Question

How is infrared spectroscopy used in forensic science?

Answer 1

Hint :Infrared spectroscopy can be defined as the measurement of the interaction of the infrared radiation with the matter by absorption, emission or the reflection. The method or the technique of infrared spectroscopy is conducted with an instrument called an infrared spectrometer in which it produces infrared spectrum.

Complete Step By Step Answer:
Since most of the evidence which is left at the crime scenarios consists of the organic compounds and therefore infrared spectroscopy is used for investigations. Substances such as paint, ink, sweat, fuels and hair can be identified.
Now, with the new advanced technology sample sizes can be very small and the portable IR (infrared) equipment can be taken directly to a scene for on the site analysis.
At the crime sites, fibers of various other kinds are also found such as some fabric, animals, human hair and any other sources. Infrared spectroscopy makes it possible to identify the type of the fiber found.
For example- if it is the hair then it can be compared with the known sample and possibly taken from the suspect. It is also possible to identify if the hair has the traces of the hairspray or the other hair-styling products. Here the sample size can be very small.

Note :
Infrared spectroscopy is used to study and identify chemical substances or the functional groups in any form such as solid, liquid or gaseous. The common laboratory instrument which uses this technique is the Fourier transform infrared spectrum.