ARSC/GEOL 2110
Physical Science of the Earth System
Assignments
Fall 2001

Lab report is due November 7th, 2001.

Useful resources: Ch. 6 pp. 112-125, and Ch. 7, pp. 149-151, Blue Planet Appendix C, Blue Planet

1. Summarize your findings from Part I of the crystal growth lab in one or two sentences. (Hint: they will need to be well-crafted, information-packed sentences!)

2. Describe the experiment your group came up with in Part II, using the following format:
a) State your question or hypothesis (1 sentence).
b) Summarize what you did to investigate your question or hypothesis. (1-3 sentences)
c) Summarize your results and interpret them (what you found out from your experiment and what it means). (2-4 sentences)

3. How do laboratory experiments on growing crystals help interpret whether a natural igneous rock is intrusive or extrusive? That is, what's the connection between the lab observations and observations of field samples? Explain.

4. Explain why, when the elements are combined into ionic compounds, the element Na tends to form an Na+ cation but the element O tends to form a O2- anion.

5. Why do cations and anions alternate in space in ionic compounds such as NaCl or Cu2O?

6. How does the microscopic (atomic-scale) crystal structure affect the macroscopic (ordinary scale) physical properties of a mineral? Explain, using the forms of carbon as an example.

7. Explain why silicate (SiO44-) ions can form such a variety of mineral structures (chains, sheets, 3-D networks, etc.).

8. At the microscopic level, what's the difference between a rock composed of crystalline minerals, such as granite, and a glassy rock such as obsidian? Explain.

9. Did using the models help you learn? Describe one or two specific concepts or ideas that were clarified for you by working with the crystal models, or if no ideas were clarified, describe one or two specific concepts that you are having difficulty with.