Police Dispatcher Practice Test

The Marquis test is a simple and well-established chemical test used primarily for the identification of various narcotics. It involves the use of a reagent that reacts specifically with certain alkaloids and other substances found in drugs. When the reagent is applied to a sample, it produces a color change that is characteristic of the specific substance being tested for.

For example, a purple color indicates the presence of heroin, while a color change to orange-red may indicate the presence of amphetamines. This capability makes the Marquis test particularly valuable in law enforcement settings for quick field identification of suspected narcotics, aiding in the appropriate course of action.

The other options — testing for alcohol content, explosive substances, or counterfeit items — are not within the scope of what the Marquis test is designed to detect, as each of these items requires entirely different testing methods and reagents specific to those substances.