research paper on the long process of forensic investigation.
Need an research paper on the long process of forensic investigation. Needs to be 8 pages. Please no plagiarism. Forensic scientists employ several tests and techniques to provide the evidence needed for the case. Analysis of samples is necessary to identify, quantify and drug profiling. The materials previously collected, 100 grams of white powder, the trace samples from the clothing of the suspects, the cling film and the mirror will all be subjected to analysis.
Prior to the presumptive tests, physical description and sampling will be done. The physical characteristics such as texture, powder particle size, color, odor, taste, and weight will be physically defined before a sample for analysis will be secured. It will be weighed and thoroughly homogenized before a sample was taken.
The presumptive analysis will provide the identification of the white powder collected from the table. Trace samples from the suspects’ clothing can directly be analyzed using confirmatory tests. The color test will bring initial data for the powder’s identity. Specific color changes give a positive result for the powder’s identity. An intense blue-violet color when the powder is made to react with 1% cobalt acetate and 5% isopropylamine in methanol of the Dillie-Koppanyi test will identify it as a barbiturate. Marquis test using a dilute solution of methanal in sulphuric acid can give two types of results. if the color changed to purple, the powder is heroin-based, if the test however yields an orange-brown colour, the powder is an amphetamine. Treating it with a Duquenois-Levine test reagent and a purple color resulted, the powder is positive as marijuana. In Scott test, in which a solution of cobalt chloride is added in a 50:50 mixture of water and glycerol, a blue color positively identifies cocaine. This positive result can be confirmed by adding concentrated hydrochloric acid, the liquid goes pink and then adding chloroform the blue reappears in the chloroform layer. Blue-purple in reaction with reagents of Van Urk test means the powder is LSD.