An unknown white powder was located at a crime scene. Describe an analytical scheme to identify the drug or drugs that may be present in the powder
Put steps in the proper order, and for each step, indicate whether it is a screening or confirmatory test and note why it should be used.
What will be an ideal response?
Answer should include points such as the following:
a. Chromatography, a screening test, can be used to separate the unknown mixture into its components. This is particularly useful for analyzing drug specimens because drugs may have been diluted with practically any material by the seller in order to increase the quantity of product available to prospective customers.
b. Various color tests or ultraviolet/visible spectrophotometry can be used as screening tests to presumptively identify which drug or drugs may be present in the powder. This can narrow down the number of substances to be searched for, and possibly confirmed, in later testing.
c. Infrared spectrophotometry and gas chromatography/mass spectrometry analysis are both confirmatory tests with sensitivity and specificity sufficient enough to identify drugs in the powder. GC/MS is most preferred because (1) it can resolve a highly complex mixture into its components within a brief time period; (2) it is extremely sensitive; and (3) it can yield quantitative results. Connection of the GC/MS unit to a computer further facilitates the comparison of spectra for identifcation purposes.
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An important housing authority survey finding told Tulsa patrol officers that 86 percent of the occupants lived in households that:
A) had no heat or air B) had no family income C) had at least five or more family members D) were headed by single females
What is the difference between forward spatter and back spatter? Which is more likely to be deposited on the object or person creating the impact?
What will be an ideal response?
A rule of thumb to follow is that the sample size should be which of the following in relation to the population?
a. 1/5th. b. 1/20th. c. 1/10th. d. 1/100th.
Guilty knowledge refers to:
a. when an researcher is aware that a respondent engaged in a wrongful behavior. b. when a researcher alters his findings to make them more interesting. c. when an IRB knows that a researcher engaged in ethical violation but does not sanction the researcher. d. when a researcher’s biases affect her coding of information.