LAB: DETERMINING THE DENSITY OF THE EARTH

LAB: DETERMINING THE DENSITY OF THE EARTH

Objective : to calculate and compare the densities of earth materials.

Materials: Triple-beam balance graduated cylinder
Water rock samples of granite, basalt and slate
Sample of iron (Fe)

Hypothesis - _____________________________________________________________

Procedure:

SAMPLE Volume of rock Volume of Volume of MASS Density
& water water alone rock alone (g) (g/cm3)

Granite

Basalt

Slate

Iron

CLASS DATA

CLASS DATA

g/cm³ g/cm³ g/cm³
AVERAGE DENSITY DENSITY DENSITY

GROUP OF ROCKS OF IRON OF EARTH
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1.
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2.
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3.
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4.
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5.
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6.
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7.
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8.
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9.
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10.
TOTAL
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AVERAGE

QUESTIONS AND CONCLUSIONS

1. Using only the rock samples (basalt, granite, slate) find the average density of rock. SHOW WORK AND INCLUDE UNITS!

2. Compare the density of iron to the average rock density that was calculated in #1.

3. Take the average rock density and the density of iron. Find the average of these two numbers for both your individual data and the class averages. This calculation will give you the density of the earth. SHOW WORK AND INCLUDE UNITS!

PERSONAL DATA ___________ CLASS DATA

PERSONAL DATA ___________ CLASS DATA

4. The known density of the Earth is 5.5 g/cm3. Using your ESRT, calculate the percent deviation for both your individual data and the class data. SHOW YOUR WORK AND INCLUDE UNITS!
Personal Data _____________ Class Data

5. Using your ESRT, what layer(s) of the earth do(es) the three rock samples represent? Explain your answer.

6. Using your ESRT, what layer of the earth does the iron (Fe) sample represent?

7. Why is the mantle not represented in the above samples?

8. The denser the material, the faster the seismic wave will travel. Using the information above, predict which tectonic plates seismic waves will travel fastest through. Give an example of plates from your ESRT.

9. Using your ESRT, name 2 plates for each:

a. continental plate _____________________________, _________________________

b. oceanic plate ________________________________, _________________________

10. Locate 2 plate boundaries for each:

a. converging center _____________________________, ________________________

b. diverging center _______________________________, _______________________

11. At the converging centers, predict which plate will be subducting and which will override the other.

CONCLUSION PARAGRAPH: Write a summary paragraph that sums up your data and explains your conclusions. Write in whole sentences and be specific and clear in your explanations regarding Earth’s densities and the densities’ relevance to tectonic plates.