CRJ 320 WEEK 3 Assignment II Chapter 5 AND Chapter 6
Chapter 5 Questions
1 Define the terms element and compound and name the smallest unit of each
2. Name the three forms, or states, of matter and explain how the shape and volume of matter are expressed in each state.
3. What physical change occurs when a substance undergoes the following changes of state: (a) from liquid to solid, and (b) from liquid to gas?
4. Define sublimation. What happens to the attractive forces between molecules of a substance that undergo sublimation?
5. What is a phase and how can two different phases be distinguished from one another?
6. What is the fundamental difference between organic and inorganic substances?
7. Describe the difference between a quantitative and a qualitative determination.
8. What basic tool is most often used to characterize and identify organic materials? Why is this tool chosen for that purpose?
9. What is the greatest drawback to spectrophotometry? What technique is often employed when spectrophotometry cannot be used?
10. Briefly describe the basic chromatographic process. Be sure to explain how motion is important to the process.
11. What three chromatographic processes are most applicable for solving analytical problems typically encountered in the crime laboratory? What is the main advantage of each?
12. What is electrophoresis and what is it most widely used for?
13. What is color? What determines the color of an opaque object?
14. What two models do scientists use to explain the nature of light? Under what conditions does each model best describe the behavior of light?
15. What is Beer- law and what analytical technique is based on it?
Chapter 6 Questions:
1. What is a trace element and why are trace elements important in analyzing physical evidence?
2. Explain how the analysis of trace elements was important to the investigation of the assassination of President John F. Kennedy.
3. What two characteristics of elements form the basis of the analytical techniques of emission spectroscopy and atomic absorption spectrophotometry ?
4. Describe the difference between a continuous spectrum and a line spectrum. Which is most helpful in identifying a particular element and why?
5. How does the quantity of light absorbed during atomic absorption spectrophotometry relate to the concentration of the absorbing element? What is the significance of this relationship for the forensic scientist?