Layers of the Earth Lab

Name: _____________________________________________________ Period: _______ Date: ________________ Layers of the Earth: Density Lab Purpose: Many of Earth’s processes are due to different densities of materials within the Earth. Getting a feel for the average densities of different earth materials will give you an understanding of the driving factor behind some of these processes. Materials: Graduated cylinders (500 or 1000mL); electronic balances; water; string for lowering sample into graduated cylinder; various rock and mineral samples Procedures: 1) Use the balance to find the mass of the material. 2) Pour enough water into the large beaker for the rock samples. Measure and record the volume of just the water. This is the initial volume. You will have to re-measure this volume before each sample. 3) Carefully place the material being tested in the graduated cylinder. You may tie a string around the sample to help lower the sample into the graduated cylinder. Find the volume of the water plus the material. This is the final volume. Subtract the initial volume from the final volume. This is the volume of the material. Note that 1 mL = 1 cm3. 4) Divide mass by the volume to find the density. 5) Calculate the percent error: Your Value – Actual Value = Error Value Data: Mass of material (g) Initial water vol. (mL) THEN Final water vol. (mL) Error Value ÷ Actual Value x 100 = % Error Volume of material (mL) Density of material (g/mL or g/cm3) Yours Actual Hematite (core) Olivine (mantle rock/asthenosphere) Basalt (oceanic crust/lithosphere) Granite (continental crust/lithosphere) Obsidian (continental crust/lithosphere) Graph interpretation: Refer to the Inferred Properties of Earth’s Interior to answer the following questions. 1) What two layers make up the lithosphere? _________________ and __________________ 2) Name the two elements that compose the inner core: ______________________________ 3) What is the temperature at a depth of 3000 km? ____________________ 4) What is the temperature at a depth of 500 km? _____________________ 5) What is the pressure at a depth of 5000 km? _______________________ 6) What is the pressure at a depth of 500 km? ________________________ % Error 7) Name the layer where the temperature is 4000C: ____________________ 8) Name the layer where the pressure is 3.5 million atmospheres: ______________________ 9) Name the layer where the temperature is 6000C: ________________________________ 10) Which layer is completely liquid?_______________. Explain how you can tell by looking at the chart: Use the same diagram to fill in the two tables below: Layer Continental Crust Oceanic Crust Layer Density (g/cm3) Density Range (g/cm3) Rock type Pressure Range (millions of atmospheres) Temperature Range (°C) Mantle Outer Core Inner Core Analysis questions: Answer in complete sentences. 1) How do the densities you measured for your rock samples (granite, basalt, etc.) compare with the actual values? (look at your % error!) What do you think are some sources of error with your measurements? 2) Earth’s core is believed to be composed primarily of an iron-nickel alloy. Compare the values you got for the density of Hematite (iron) to the density of the core. Why is there such a difference? Use the inferred properties of Earth’s interior graph to help. Conclusion: Write a brief paragraph telling how your data helps explain the internal structure of the Earth: Inferred Properties of Earth’s Interior