FIS 201 Exam #4 Questions with Correct Answers Latest Update 2025/2026
What is the primary focus of forensic chemistry? - Answers The process of identifying unknown
materials.
What types of evidence do forensic chemists analyze? - Answers Unknown trace evidence,
drugs, arson, and explosives residues.
What is the typical salary range for a forensic chemist? - Answers $45,000 to $100,000 per year.
What is the first step in the analytical process for forensic evidence? - Answers Prepare
samples of unknown evidence.
How can a forensic chemist conclude that reference and evidence samples are the same? -
Answers If data from the reference matches the data from the evidence.
What is an alternative analytical process in forensic chemistry? - Answers Comparing output
data to a reference library instead of running an independent sample.
What are the benefits of using a reference library in forensic analysis? - Answers It is faster and
more efficient for identifying unknown materials.
What is spectroscopy? - Answers A method that examines how molecules reflect light based on
electron behavior in atomic shells.
What are the drawbacks of using spectroscopy? - Answers It does not provide specific chemical
structures and does not quantify amounts.
What are the three types of spectroscopy mentioned? - Answers UV-Vis, Infrared (IR), and
Raman spectroscopy.
What does UV-Vis spectroscopy examine? - Answers Absorbance and reflection of light less
than 400 nm.
What is the purpose of Infrared (IR) spectroscopy? - Answers To identify chemical bonds by
examining absorbance and reflection of light between 400 nm and 700 nm.
What does Raman spectroscopy analyze? - Answers Scattered reflection of light to identify
chemical bonds.
What is Thin Layer Chromatography (TLC)? - Answers A method that separates mixtures into
colored components using a solid stationary phase and a liquid mobile phase.
What is the principle behind chromatography? - Answers Mixtures separate based on their
interaction with a substrate, with smaller molecules moving faster than larger ones.
What are the types of chromatography mentioned? - Answers Thin Layer Chromatography, Gas
, Chromatography, and Liquid Chromatography.
What is Mass Spectrometry used for in forensic analysis? - Answers To identify the molecular
structure of unknown chemicals by measuring mass over charge.
What is the significance of molecular fragmentation in mass spectrometry? - Answers Complex
molecules break up predictably at weak bonds, allowing for identification of fragments.
What are the limitations of mass spectrometry? - Answers It does not cope well with mixtures
and does not quantify amounts.
How can chromatography and mass spectrometry be combined? - Answers By connecting the
output of a chromatograph to the input of a mass spectrometer for purifying and quantifying
samples.
What is the role of a human chemist in the analytical process? - Answers To compare data from
reference libraries with unknown evidence and make qualified decisions.
What is the purpose of using a mobile phase in chromatography? - Answers To carry a sample
across a stationary phase for separation.
What is the importance of the height and depth on the y-axis in spectroscopy? - Answers It
should be relatively consistent between chemicals, indicating the presence of specific bonds.
What is the role of capillary action in Thin Layer Chromatography? - Answers It carries the
sample up the plate by the process of absorbance.
What is the primary function of a mass spectrometer? - Answers To measure the mass-to-
charge ratio of ions to identify chemical structures.
What is the significance of the x-axis in mass spectrometry? - Answers It represents mass over
charge, while the y-axis shows the abundance of ions.
What is the main advantage of using analytical chemistry in forensics? - Answers It allows for
the precise identification of unknown substances, which is crucial for legal investigations.
What is a drug? - Answers A substance that changes bodily function or mental state; may be
natural or synthetic.
What is a medicine? - Answers A drug where changes of bodily function are beneficial or
desirable.
What is a toxin? - Answers A drug that disrupts bodily function and can lead to death.
What is recreational drug use? - Answers The use of drugs taken for pleasure.
What is illicit drug use? - Answers The use of drugs outside of medicinal or legal use.
What is the primary focus of forensic chemistry? - Answers The process of identifying unknown
materials.
What types of evidence do forensic chemists analyze? - Answers Unknown trace evidence,
drugs, arson, and explosives residues.
What is the typical salary range for a forensic chemist? - Answers $45,000 to $100,000 per year.
What is the first step in the analytical process for forensic evidence? - Answers Prepare
samples of unknown evidence.
How can a forensic chemist conclude that reference and evidence samples are the same? -
Answers If data from the reference matches the data from the evidence.
What is an alternative analytical process in forensic chemistry? - Answers Comparing output
data to a reference library instead of running an independent sample.
What are the benefits of using a reference library in forensic analysis? - Answers It is faster and
more efficient for identifying unknown materials.
What is spectroscopy? - Answers A method that examines how molecules reflect light based on
electron behavior in atomic shells.
What are the drawbacks of using spectroscopy? - Answers It does not provide specific chemical
structures and does not quantify amounts.
What are the three types of spectroscopy mentioned? - Answers UV-Vis, Infrared (IR), and
Raman spectroscopy.
What does UV-Vis spectroscopy examine? - Answers Absorbance and reflection of light less
than 400 nm.
What is the purpose of Infrared (IR) spectroscopy? - Answers To identify chemical bonds by
examining absorbance and reflection of light between 400 nm and 700 nm.
What does Raman spectroscopy analyze? - Answers Scattered reflection of light to identify
chemical bonds.
What is Thin Layer Chromatography (TLC)? - Answers A method that separates mixtures into
colored components using a solid stationary phase and a liquid mobile phase.
What is the principle behind chromatography? - Answers Mixtures separate based on their
interaction with a substrate, with smaller molecules moving faster than larger ones.
What are the types of chromatography mentioned? - Answers Thin Layer Chromatography, Gas
, Chromatography, and Liquid Chromatography.
What is Mass Spectrometry used for in forensic analysis? - Answers To identify the molecular
structure of unknown chemicals by measuring mass over charge.
What is the significance of molecular fragmentation in mass spectrometry? - Answers Complex
molecules break up predictably at weak bonds, allowing for identification of fragments.
What are the limitations of mass spectrometry? - Answers It does not cope well with mixtures
and does not quantify amounts.
How can chromatography and mass spectrometry be combined? - Answers By connecting the
output of a chromatograph to the input of a mass spectrometer for purifying and quantifying
samples.
What is the role of a human chemist in the analytical process? - Answers To compare data from
reference libraries with unknown evidence and make qualified decisions.
What is the purpose of using a mobile phase in chromatography? - Answers To carry a sample
across a stationary phase for separation.
What is the importance of the height and depth on the y-axis in spectroscopy? - Answers It
should be relatively consistent between chemicals, indicating the presence of specific bonds.
What is the role of capillary action in Thin Layer Chromatography? - Answers It carries the
sample up the plate by the process of absorbance.
What is the primary function of a mass spectrometer? - Answers To measure the mass-to-
charge ratio of ions to identify chemical structures.
What is the significance of the x-axis in mass spectrometry? - Answers It represents mass over
charge, while the y-axis shows the abundance of ions.
What is the main advantage of using analytical chemistry in forensics? - Answers It allows for
the precise identification of unknown substances, which is crucial for legal investigations.
What is a drug? - Answers A substance that changes bodily function or mental state; may be
natural or synthetic.
What is a medicine? - Answers A drug where changes of bodily function are beneficial or
desirable.
What is a toxin? - Answers A drug that disrupts bodily function and can lead to death.
What is recreational drug use? - Answers The use of drugs taken for pleasure.
What is illicit drug use? - Answers The use of drugs outside of medicinal or legal use.
