forensics chapter 5

Absorption spectrum

graph produced by a spectrophotometer that depicts the absorption of light as a function of wavelength or frequency

Anabolic steroids

synthetic compounds chemically related to the male sex hormone testosterone that are used to promote muscle growth

Analgesic

a substance that lessens or eliminates pain

Beer's law

absorption of light taken up at a single frequency is directly proportional to the concentration of the absorbing species A = kc

Chromatography

any of several analytical techniques for separating organic mixtures into their components by attraction to a stationary phase while being propelled by a moving phase

Confirmation

a single test that specifically identifies a substance

Depressant

a substance that slows down, or depresses, the functions of the central nervous system

Dillie-Koppanyi

screens for Barbiturates where it turns violet-blue

Duquenois-Levine

test for marijuana, shows purple after a series of chemical solution with chloroform being the last step

Fluoresce

to emit visible light when exposed to light of a shorter wavelength—that is, ultraviolet light

Gas-Chromatography (GC)

separates mixtures based on their distribution between a stationary liquid phase and a moving gas phase, where the moving phase is called the carrier gas which flows through a column constructed of stainless steel or glass and the stationary phase is a thin film of liquid within the column

Hallucinogen

a substance that induces changes in normal thought processes, perceptions, and moods

Infrared

invisible short frequencies of light before red in the visible spectrum

IR spectrophotometry

provides a far more complex pattern the UV spectrophotometry because different materials have distinctly different infrared spectra, each IR spectrum is equivalent to a fingerprint

ion

an atom or molecule bearing a positive or negative charge

Marquis

the reagent turns purple in the presence of heroin and morphine and most opium derivatives. Can also become orange brown when mixed with amphetamines and methamphetamines

Mass spectrometry

characterizes organic molecules by observing their fragmentation pattern after their collision with a beam of high energy electrons

Microcrystalline test

a test that identifies a specific substance based on the color and shape of crystals formed when the substance is mixed with specific reagents

Monochromatic light

light having a single wavelength or frequency

Monochromator

a device for isolating individual wavelengths or frequencies of light

Narcotic

a drug that induces sleep and depresses vital body functions such as blood pressure, pulse rate, and breathing rate

Physical dependence

physiological need for a drug brought about by its regular use and characterized by withdrawal sickness when administration of the drug is abruptly stopped

Psychological dependence

the conditioned use of a drug caused by underlying emotional needs

Qualitative identification

relates to the identity of the material and requires the determination of numerous properties using a variety of analytical techniques

Quantitative identification

refers to the percentage combination of the components of the mixture is usually accomplished by precise measurement of a single material

Schedule I

drugs have a high potential for abuse and have no currently accepted medical use such as heroin, marijuana, methaqualone, and LSD.

Schedule II

drugs have a high potential for abuse and have medical use with severe restrictions such as cocaine, PCP, and most amphetamine and barbiturate prescriptions

Schedule III

drugs have less potential for abuse and a currently accepted medical use such as all barbiturate prescriptions not covered under Schedule II, such as codeine and anabolic steroids

Schedule IV

drugs have a low potential for abuse and have a current medical use such as darvon, phenobarbital, and some tranquilizers such as diazepam (valium) and chlordiazepoxide (librium)

Schedule V

drugs must show low abuse potential and have medical use such as opiate drug mixtures that contain nonnarcotic medicinal ingredients

Scott Test

color test for cocaine which turns cobalt thiocyanate solution blue. Upon the addition of HCl the blue changes to pink. Upon the addition of chloroform, if cocaine is present , the blue color reappears in the chloroform layer

Screening test

a preliminary test used to reduce the number of possible identities of an unknown substance

Spectrophotometry

an analytical method for identifying a substance by its selective absorption of different wavelengths of light

Stimulant

a substance that speeds up, or stimulates, the central nervous system

Thin-Layer Chromatography (TLC)

uses a solid stationary phase and a moving liquid phase to separate the constitutes of a mixture

Ultraviolet

invisible long frequencies of light beyond violet in the visible spectrum

Van Urk

reagent turns bluepurple in the presence of LSD

Withdrawal sickness

(abstinence syndrome): body chills, vomiting, stomach cramps, convulsions, insomnia, pain and hallucinations