1. Using the glossary of your book, please look up the definitions of the following words
a. Aphanitic texture -
b. Phaneritic texture -
c. Phenocryst -
d. Groundmass -
2. Question: How does temperature affect the formation of crystals?
3. Hypothesis:
4. Results:
Fill in the tables below. If any of your samples did not produce crystals, simply enter "no crystals". For size of crystals, I am only looking for a comparative adjective (e.g., big, small, tiny), for the appearance of crystals, I am looking for things like "they are all bunched together" or "there is just one big crystal".
Crystal Formation Table
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Sample
(after 4 hours)
|
Sample location
|
Size of crystals
|
Appearance of Crystals
|
Photo of Crystals
|
|
1
|
Room temperature
|
|
|
|
|
2
|
Refrigerator
|
|
|
|
|
3
|
Freezer
|
|
|
|
|
Sample
(overnight)
|
Sample location
|
Size of crystals
|
Appearance of Crystals
|
Photo of Crystals
|
|
1
|
Room temperature
|
|
|
|
|
2
|
Refrigerator
|
|
|
|
|
3
|
Freezer
|
|
|
|
5. Analyze the results
a. Was your prediction correct? Explain.
b. Write three sentences that compare the size and shape of the crystals in the samples.
6. Draw conclusions
|
|
Granite
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Basalt
|
Obsidian
|
|
How did the rock sample form?
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|
|
|
|
Rate of cooling
|
|
|
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