SLO Earth Science

H.B.1A.6: Construct explanationsof phenomena using (1) primary or secondary scientific evidence and models, (2) conclusions from scientific investigations, (3) predictions based on observations and measurements, or (4) data communicated in graphs, tables, or diagrams.

H.E.2B.The solar system consists of the Sun and a collection of objects of varying sizes and conditions – including planets and their moons – that have predictable patterns of movement. These patterns can be explained by gravitational forces and conservation laws, and in turn explains many large-scale phenomena observed on Earth. Kepler’s laws describe common features of the motions of orbiting objects, including their elliptical paths around the Sun. The solar system appears to have formed from a disk of dust and gas, drawn together by gravity.

H.E.3A.5 Analyze and interpret data to describe the physical and chemical properties of minerals and rocks and classify each based on the properties and environment in which they were formed.

H.E.5A Weather is the condition of the atmosphere at a particular location at a particular time. Weather is primarily determined by the angle and amount (time) of sunlight. Climate is the general weather conditions over a long period of time and is influenced by many factors.

H.E.5A.7 Construct scientific arguments to support claims of past changes in climate caused by various factors (such as changes in the atmosphere, variations in solar output, Earth’s orbit, changes in the orientation of Earth’s axis of rotation, or changes in the biosphere). Assessment

H.B.1.A.4 Analyze and interpret data from informational texts, observations, measurements, or data collected from investigations using a range of methods (such as tabulation, graphing, or statistical analysis) to (1) reveal patterns and construct meaning (2) support or refute hypotheses, explanations, claims, or designs (3) or evaluate the strength of conclusions.

Passage I

Unmanned spacecraft taking images of Jupiter's moon Europa have found its surface to be very smooth with few meteorite craters. Europa's surface ice shows evidence of being continually resmoothed and reshaped. Cracks, dark bands, and pressure ridges (created when water or slush is squeezed up between 2 slabs of ice) are commonly seen in images of the surface. Two scientists express their views as to whether the presence of a deep ocean beneath the surface is responsible for Europa's surface features.

Scientist 1

A deep ocean of liquid water exists on Europa. Jupiter's gravitational field produces tides within Europa that can cause heating of the subsurface to a point where liquid water can exist. The numerous cracks and dark bands in the surface ice closely resemble the appearance of thawing ice covering the polar oceans on Earth. Only a substantial amount of circulating liquid water can crack and rotate such large slabs of ice. The few meteorite craters that exist are shallow and have been smoothed by liquid water that oozed up into the crater from the subsurface and then quickly froze.

Jupiter's magnetic field, sweeping past Europa, would interact with the salty, deep ocean and produce a second magnetic field around Europa. The spacecraft has found evidence of this second magnetic field.

Scientist 2

No deep, liquid water ocean exists on Europa. The heat generated by gravitational tides is quickly lost to space because of Europa's small size, as shown by its very low surface temperature (–160°C). Many of the features on Europa's surface resemble features created by flowing glaciers on Earth. Large amounts of liquid water are not required for the creation of these features. If a thin layer of ice below the surface is much warmer than the surface ice, it may be able to flow and cause cracking and movement of the surface ice. Few meteorite craters are observed because of Europa's very thin atmosphere; surface ice continually sublimes (changes from solid to gas) into this atmosphere, quickly eroding and removing any craters that may have formed.

  1. Which of the following best describes how the 2 scientists explain how craters are removed from Europa's surface?
  2. Scientist 1 Scientist 2
  3. A.Sublimation Filled in by water
  4. B.Filled in by water Sublimation
  5. C.Worn smooth by wind Sublimation
  6. D.Worn smooth by wind Filled in by water
  1. According to the information provided, which of the following descriptions of Europa would be accepted by both scientists?
  2. F. Europa has a larger diameter than does Jupiter.
  3. G. Europa has a surface made of rocky material.
  4. H. Europa has a surface temperature of 20°C.
  5. J. Europa is completely covered by a layer of ice.
  6. With which of the following statements about the conditions on Europa or the evolution of Europa's surface would both Scientist 1 and Scientist 2 most likely agree? The surface of Europa:
  7. A. is being shaped by the movement of ice.
  8. B. is covered with millions of meteorite craters.
  9. C. is the same temperature as the surface of the Arctic Ocean on Earth.
  10. D. has remained unchanged for millions of years.
  11. Which of the following statements about meteorite craters on Europa would be most consistent with both scientists' views?
  12. F. No meteorites have struck Europa for millions of years.
  13. G. Meteorite craters, once formed, are then smoothed or removed by Europa's surface processes.
  14. H. Meteorite craters, once formed on Europa, remain unchanged for billions of years.
  15. J. Meteorites frequently strike Europa's surface but do not leave any craters.
  16. Scientist 2 explains that ice sublimes to water vapor and enters Europa's atmosphere. If ultraviolet light then broke those water vapor molecules apart, which of the following gases would one most likely expect to find in Europa's atmosphere as a result of this process?
  17. A. Nitrogen
  18. B. Methane
  19. C. Chlorine
  20. D. Oxygen
  1. Based on the information in Scientist 1's view, which of the following materials must be present on Europa if a magnetic field is to be generated on Europa?
  2. F. Frozen nitrogen
  3. G. Water ice
  4. H. Dissolved salts
  5. J. Molten magma
  6. Assume Scientist 2's view about the similarities between Europa's surface features and flowing glaciers on Earth is correct. Based on this assumption and the information provided, Earth's glaciers would be least likely to exhibit which of the following features?
  7. A. Pressure ridges
  8. B. Cracks
  9. C. Meteorite craters
  10. D. Dark bands
  11. Two scientists express their views as to whether the presence of a deep ocean beneath the surface is responsible for Europa's surface features. Evaluate both explanations and decide which scientist’s explanation seems to be the most plausible. After you have chosen defend your choice with your knowledge concerning the planets in our solar system.

Passage 2

Spent fuel (SF), a radioactive waste, is often buried underground in canisters for disposal. As it decays, SF generates high heat and raises the temperature of the surrounding rock, which may expand and crack, allowing radioactivity to escape into the environment. Scientists wanted to determine which of 4rock types—rock salt, granite, basalt, or shale—would be least affected by the heat from SF. The thermal conductivity (how well heat is conducted through a material) and heating trends of the 4rock types were studied.

Study 1

Fifty holes, each 0.5m across and 20m deep, were dug into each of the following: a rock salt deposit, granite bedrock, basalt bedrock, and shale bedrock. A stainless steel canister containing 0.4metric tons of SF was buried in each hole. The rock temperature was measured next to each canister after 1year had passed. The results are shown in Table1, along with the typical thermal conductivity of each rock type, in Watts per meter per °C (W/m°C), at 25°C. The higher the thermal conductivity, the more quickly heat is conducted through the rock and away from the canisters.

Table 1
Rock / Thermal conductivity
(W/m°C) / Rock temperature
(°C)*
*All rock types had an initial temperature of 10°C.
Rock salt
Granite
Basalt
Shale / 5.70
2.80
1.26
1.57 / 110
121
165
146

Study 2

The scientists determined the thermal conductivity of the 4rock types at a number of different temperatures between 0°C and 400°C. The results are shown in Figure1.

Figure 1

Study 3

The scientists calculated the temperature increase that would be expected over a period of 100,000yr in each rock type at a point within a site holding buried SF. The results are shown in Figure2.

Figure 2

Table and figures adapted from J. S. Y. Wang, D. C. Mangold, and C. F. Tsang, "Thermal Impact of Waste Emplacement and Surface Cooling Associated with Geologic Disposal of High-Level Nuclear Waste." ©1988 by Springer-Verlag New York Inc.

  1. According to Study2, the thermal conductivity of rock salt measured at a temperature of 500°C would be closest to which of the following values?
  2. A. 1.0 W/m°C
  3. B. 2.0 W/m°C
  4. C. 3.5 W/m°C
  5. D. 4.0 W/m°C
  6. According to Study3, if another set of temperatures had been calculated for a time 1,000,000years in the future, the calculated temperature increase in any of the 4rock types would most likely be closest to:
  7. F.0°C
  8. G. 10°C.
  9. H. 20°C.
  10. J. 30°C.
  11. Welded tuff (another rock type) has a thermal conductivity of 1.8 W/m°C at 25°C. If measurements of the temperature of this rock type adjacent to SF canisters were taken as in Study1, the recorded temperature would be closest to:
  12. A. 100°C.
  13. B. 110°C.
  14. C. 120°C.
  15. D. 130°C.
  16. According to the results of Study1, which of the following best describes the relationship between thermal conductivity and rock temperature? As thermal conductivity increases, the rock temperature recorded adjacent to buried SF canisters:
  17. F. decreases only.
  18. G. increases only.
  19. H. increases, then decreases.
  20. J. remains the same.
  21. Based only on the information provided, which of the following rock types would be the safest in which to burySF?
  22. A. Rock salt
  23. B. Granite
  24. C. Basalt
  25. D. Shale
  26. Which of the following procedures, in addition to Studies1, 2, and3, would best test whether the amount of heat generated by SF is related to the mass of the SF?
  27. F. Following the design of Study1 but using concrete canisters containing 0.4metric tons of SF
  28. G. Following the design of Study1 but using stainless steel canisters containing 0.8metric tons of SF
  29. H. Following the design of Study2 but determining the thermal conductivities of twice as much of each rock type
  30. J. Following the design of Study3 but determining the rock temperatures 0.5km from the sites of SFburial
  31. Spent Fuel rods have become a large environmental problem around the world. Using your knowledge concerning human impact on the environment design a method of disposal that would cause the least amount of harm to the Earth.

Passage 3

The Sun's path from sunrise to sunset varies with the time of year. A student performed the following experiments on three clear, sunny days at three- or four-month intervals throughout the course of a year to study the path of the Sun through the sky.

Experiment 1

At a chosen Northern Hemisphere location, the student placed a stick vertically into the ground so that 1 meter of its length was left above ground. The student knew that the length of the shadow was related to the height of the Sun above the horizon and that the shadow would point away from the direction of the Sun. The length in meters (m) and direction of the shadow cast by the stick were measured one hour after sunrise (Shadow A), at mid-morning (B), at noon (C), at mid-afternoon (D), and one hour before sunset (E) on each of the three days. The direction of each shadow was determined by placing a magnetic compass at the base of the stick and aligning the north arrow with the north mark on the compass. The direction of each shadow was then determined by a comparison with the compass face markings. The results are recorded in Table 1.

Table 1
Shadow / Day 1 / Day 2 / Day 3
Length
(m) / Shadow
direction / Length
(m) / Shadow
direction / Length
(m) / Shadow
direction
A / 5.0 / SW / 8.6 / NW / 6.8 / W
B / 1.2 / W / 2.9 / NNW / 1.7 / NW
C / 0.3 / N / 2.3 / N / 0.9 / N
D / 1.2 / E / 3.0 / NNE / 1.8 / NE
E / 5.0 / SE / 8.6 / NE / 6.9 / E

Experiment 2

The following year, the student repeated Experiment 1 at a chosen location in the Southern Hemisphere. The results are in Table 2.

Table 2
Shadow / Day 1 / Day 2 / Day 3
Length
(m) / Shadow
direction / Length
(m) / Shadow
direction / Length
(m) / Shadow
direction
A / 9.0 / SW / 5.0 / NW / 6.9 / W
B / 3.2 / SSW / 1.1 / W / 1.8 / SW
C / 2.5 / S / 0.3 / S / 1.0 / S
D / 3.2 / SSE / 1.1 / E / 1.8 / SE
E / 9.1 / SE / 5.0 / NE / 6.9 / E

Following are some act sample questions on the above passage:

14.Which of the following was a constant in both experiments?

  1. Length of vertical stick exposed
  2. Shadow direction
  3. Day of the year
  4. Shadow length

15.If the experiments were repeated after pounding the stick farther into the ground so that only 0.5 m was exposed, how would this affect the shadow lengths?

  1. They would be twice as long as those in the original experiments.
  2. They would be one-and-one-half times as long as those in the original experiments.
  3. They would be one-half as long as those in the original experiments.
  4. They would be one-fourth as long as those in the original experiments.
  1. Which of the following graphs best represents the relationship between the length of the stick's shadow and the time of day?

A
/ B

C
/ D

  1. When the Sun is at an altitude 45o above the horizon, a vertical object will cast a shadow with a length equal to the object's height. Which of the following days included a measurement taken when the Sun was at an altitude of 45o?
  2. Day 1 in Experiment 1
  3. Day 1 in Experiment 2
  4. Day 2 in Experiment 1
  5. Day 3 in Experiment 2
  6. Which of the following statements is best supported by the direction of Shadow A on each of the three days in Experiment 1?
  7. The direction of sunrise along the horizon varies throughout the year.
  8. Shadows never point due south in the Northern Hemisphere.
  9. Shadows never point due north in the Northern Hemisphere.
  10. The Sun's brightness varies throughout the year.
  11. Based on the shadow directions in these experiments, which of the following best describes the difference between the apparent path of the Sun as seen from the observation points in the Northern and Southern Hemispheres?
  12. The Sun travels a more southerly path in the Southern Hemisphere than in the Northern Hemisphere.
  13. The Sun travels a more northerly path in the Southern Hemisphere than in the Northern Hemisphere.
  14. The Sun rises in the East and sets in the West in the Northern Hemisphere, but the opposite is true in the Southern Hemisphere.
  15. The Sun rises in the West and sets in the East in the Northern Hemisphere, but the opposite is true in the Southern Hemisphere.

Passage 6

Several methods were investigated to reduce pollution emissions from a steel mill smokestack. Steel is mostly iron (Fe), but it also contains carbon (C). Impurities containing sulfur (S), nitrogen (N), or phosphorus (P) form gaseous compounds with oxygen that become pollutants. The smoke contains these pollutants and also tiny dust particles that pollute the air, are blown around by the wind, and eventually fall to the ground.

Method 1

Steel mill smoke was passed across a set of electrified plates in the smokestack. The electrified plates attracted the dust particles in the smoke and removed them from the emissions. The efficiency of dust particle removal, which is dependent on the size of the particles, is shown in Table 1.

Table 1
Voltage on plates
(V) / Particles removed
(%)
100 / 20
200 / 50
500 / 90
1,000 / 80
3,000 / 70

Method 2

The smoke was passed through filters of different pore size in the smokestack that trapped dust particles and also decreased the amount of smoke leaving the stack. The data are shown in Table 2.

Table 2
Filter pore size
(microns) / Particles trapped
(%) / Amount of time for filters
to drop to 50% efficiency
(hours)
1,000 / 5 / 2,000
500 / 20 / 1,000
200 / 50 / 200
100 / 80 / 25
50 / 90 / 1

Method 3

To reduce pollution by chemical means, the smokestack emissions were bubbled through solutions of concentrated alkali (solutions of OH– ions). Table 3 shows the percent of the 3 pollutants removed versus the alkali concentration.

Table 3
Alkali
concentration
(%) / S
removed
(%) / N
removed
(%) / P
removed
(%)
1 / 80 / 60 / 10
3 / 90 / 65 / 40
5 / 91 / 60 / 35
10 / 92 / 50 / 30
15 / 93 / 20 / 25

Following are some act sample questions on the above passage:

20.If the plant's smoke contained equal amounts of S, N, and P, which of the following alkali concentrations would remove the most total pollution?

  1. 1%
  2. 3%
  3. 5%
  4. 10%

21.Which of the following statements about the alkali concentration is consistent with the results of Method 3 ?

  1. A higher alkali concentration results in more P removed.
  2. A higher alkali concentration results in more S removed.
  3. A lower alkali concentration requires more filters to remove dust particles.
  4. A lower alkali concentration results in an increased time required to remove all of the chemical pollutants.

22.Based on the characteristics of the filters used in Method 2, which of the following best describes the practical problem involved in choosing the best type of smokestack filter? The filter that traps the highest percentage of particles:

  1. requires the highest voltage across the electrified plates.
  2. reacts with alkali solutions.
  3. needs to be replaced least often.
  4. needs to be replaced most often.

23.If the smokestack of the steel mill was doubled in height, what effect, if any, would this be expected to have on the removal of pollutants?

  1. Filter efficiency would decrease because dust particles could more easily fall back down the stack.
  2. Electrostatic plate efficiency would increase because voltage increases with height.
  3. Dust particles would accumulate into larger pieces and would be more easily removed from the smoke.
  4. It cannot be determined from the given information.

24.Which of the following assumptions about reducing pollution emissions is common to both Methods 1 and 2 ?

  1. Emissions can only be removed by filters.
  2. Emissions can only be removed by electrified plates.
  3. Emissions must be captured in the smokestack to be removed.
  4. Emissions must be captured after they leave the smokestack.

25.To further investigate the effects of voltage on the removal of dust particles from steel mill smoke, the scientists could use which of the following procedures?

  1. Determining where the particulate matter falls to the ground after leaving the smokestack
  2. Determining what sizes of particles are removed from the smoke at different voltages
  3. Determining how the filters react when an alkali solution is passed through them
  4. Determining how the filters react when an acid solution is passed through them

26)Mrs. Garcia's earth science class conducted an experiment on how Earth absorbed solar radiation. They placed four different sheets of colored paper around the playground: white, brown, green, and black. After 15 minutes, several students were blindfolded and then asked to figure out the color of the papers by how cool or warm they felt to the touch. All the students correctly identified the white paper as the coolest and the black paper as the warmest. They had some difficulty with the green and brown.

On Earth, the white colored paper represents areas that are ______.