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


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


The decomposition of organic matter by heat.


polymers of amino acids that play basic roles in the structures and functions of living things.


a type of protein that acts as a catalyst for certain specific reactions.


A small packet of electromagnetic radiation energy. Each one contains a unit of energy equal to the product of E=hf


A device for isolating individual wavelengths or frequencies of light.

Monochromatic light

Light having a single wavelength or frequency


invisible long frequencies of light beyond violet in the visible spectrum.


Invisible short frequencies of light before red in the visible spectrum.


An atom or molecule bearing a positive or negative charge.

Psychological dependence

Conditioned use of a drug caused by underlying emotionial needs.

Physical dependence

Physiological need for a drug that has been brought about by its regular use.


An analgesic or pain-killing substance that depresses vital body functions such as blood pressure, pulse rate, and breathing rate.


A drug or substance that lessens or eliminates pain.


A substance that induces changes in mood, attitude, thought processes, and perceptions.


A substance that depresses the functions of the central nervous system. They calm irritability and anxiety and may include sleep.


A substance taken to increase alertness or activity

Screening Test

A test that is nonspecific and preliminary in nature.


A single test that specifically identifies a substance.

Microcrystalline Tests

Tests to identify specific substances by the color and morphology of the crystals formed when the substance is mixed with specific reagents.


passage of alcohol across the wall of the stomach and small intestine into the bloodstream.


The combination of oxygen with other substances to produce new products.


Elimination of alcohol from the body in an unchanged state.


A blood vessel that carries blood away from the heart.


A blood vessel that transports blood toward the heart.


A tiny blood vessel across whose walls exchange of materials between the blood and tissues take place.


Small sacs in the lungs through whose walls air and other vapors are exchanged between the breath and the blood.

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