Free Earth and Space Sciences (5572) Practice Questions

Sample Practice Questions

Try these 10 sample questions from the Earth and Space Sciences (5572) practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1Students claim that groundwater near a landfill contains more dissolved salts than groundwater upstream. Which evidence would directly test this claim?

   1. A.Repeated dissolved-salt measurements from both locationsCorrect answer: A
   2. B.A vote on which location seems more polluted
   3. C.A diagram showing the students' preferred explanation
   4. D.A list of predictions copied from an untested model

   Explanation: The source states: "Based on empirical evidence collected through observation or experimentation" Repeated measurements of the claimed quantity at both sites directly test the empirical comparison. Opinions, a preferred illustration, and untested predictions do not provide observations of the salt concentrations.

   Reference: ETS Earth and Space Science (5572) Study Companion — p. 5, Nature of Science — Nature of scientific knowledge, empirical-evidence bullet

2. 2A dry rock fragment has a mass of 84 g and displaces 28 mL of water when fully submerged. What is its density?

   1. A.0.33 g/mL
   2. B.112 g/mL
   3. C.3.0 g/mLCorrect answer: C
   4. D.56 g/mL

   Explanation: The source states: "Density is the mass per unit volume of a substance" Density is 84/28 = 3.0 g/mL. The inverse 28/84 gives about 0.33; adding 84 and 28 gives 112, and subtracting gives 56. Addition and subtraction of unlike quantities do not calculate density.

   Reference: Water Density — Water Density, definition

3. 3Why does ordinary ice float on liquid fresh water?

   1. A.Its molecules lose mass during freezing.
   2. B.Its molecules pack more tightly during freezing.
   3. C.Its crystal structure spreads molecules farther apart.Correct answer: C
   4. D.Its buoyancy requires air bubbles trapped in crystals.

   Explanation: The source states: "The lattice arrangement allows water molecules to be more spread out than in a liquid, and, thus, ice is less dense than water." The open crystal lattice lowers ice's density without reducing molecular mass. Tighter packing would raise density; trapped air can affect a particular sample, but bubbles are not required for ordinary ice to float.

   Reference: Water Density — Ice is less dense than water

4. 4Why does the Northern Hemisphere receive stronger solar heating during its summer than during its winter?

   1. A.Earth is closer to the Sun during northern summer.
   2. B.Earth rotates more slowly during northern summer.
   3. C.Its tilt places the hemisphere more toward the Sun.Correct answer: C
   4. D.Solar energy output peaks during each northern summer.

   Explanation: The source states: "During part of the year, the northern hemisphere is tilted toward the Sun, and the southern hemisphere is tilted away." Tilt changes solar angle and day length, producing opposite seasons in the two hemispheres. Distance and solar output affect Earth as a whole rather than explaining opposite hemispheric seasons; a slower daily spin is not their cause.

   Reference: Earth Facts — Orbit and Rotation

5. 5A runoff experiment compares bare soil on a steep tray with grass-covered soil on a gentle tray. The goal is to isolate the effect of vegetation. Which change would remove the stated confounding variable?

   1. A.Measure runoff volume in a different unit
   2. B.Give both trays the same slopeCorrect answer: B
   3. C.Record only the first trial from each tray
   4. D.Average the runoff volumes of the two trays

   Explanation: The source states: "Consider possible confounding variables or effects and evaluate the investigation’s design to ensure variables are controlled." Slope varies with vegetation in the original design. Equalizing slope isolates the vegetation comparison; changing units, discarding trials, or pooling outcomes does not remove that confounding.

   Reference: ETS Earth and Space Science (5572) Study Companion — p. 18, SEP 3

6. 6Four rain samples have pH values of 4.3, 5.2, 6.1, and 7.0. Which sample is the most acidic?

   1. A.The sample with pH 4.3Correct answer: A
   2. B.The sample with pH 5.2
   3. C.The sample with pH 6.1
   4. D.The sample with pH 7.0

   Explanation: The source states: "The lower a substance's pH (less than 7), the more acidic it is" Acidity increases as pH decreases. Of the stated values, 4.3 is the lowest; 7.0 is neutral rather than most acidic.

   Reference: What is Acid Rain? — Measuring Acid Rain

7. 7Which movement of water adds to underground groundwater storage through recharge?

   1. A.Downward infiltration reaching saturated subsurface materialCorrect answer: A
   2. B.Discharge from an aquifer into a flowing stream
   3. C.Evaporation from a lake into the atmosphere
   4. D.Surface runoff entering a channel after rainfall

   Explanation: The source states: "The part that continues downward through the soil until it reaches rock material that is saturated is groundwater recharge." Recharge adds infiltrated water to the groundwater system. Discharge removes groundwater; evaporation and surface runoff follow other pathways.

   Reference: Groundwater — What Is Groundwater? — What is groundwater?

8. 8Outside eclipses, what causes the Moon's illuminated shape as seen from Earth to change through its monthly phases?

   1. A.We see different portions of its sunlit half as it orbits.Correct answer: A
   2. B.Earth's shadow gradually covers different lunar regions.
   3. C.The Moon generates different amounts of visible light.
   4. D.The Sun lights alternating fractions of the whole Moon.

   Explanation: The source states: "The Sun always illuminates half of the Moon while the other half remains dark, but how much we are able to see of that illuminated half changes as the Moon travels through its orbit." Orbital geometry changes the visible portion of the illuminated hemisphere. Earth's shadow causes eclipses, and moonlight is reflected rather than internally generated.

   Reference: Moon Phases — All Moon Phases — introductory explanation

9. 9Two models predict sediment transport at several flow speeds. Which comparison is an empirical test of their predictive accuracy?

   1. A.Agreement between the two models' predicted transport rates
   2. B.Agreement among repeated model runs with identical inputs
   3. C.Agreement with independently measured sediment-transport ratesCorrect answer: C
   4. D.Agreement with reference data generated by the model itself

   Explanation: The source states: "Design a test of a model to ascertain its reliability." Independent measured rates test the models against the external phenomenon. Agreement between models may preserve shared errors; repeatable runs show consistency, and self-generated reference data provide circular validation.

   Reference: ETS Earth and Space Science (5572) Study Companion — p. 18, SEP 2

10. 10A spacecraft transmits a radio signal across empty space. Why could a sound wave not make the same trip through that vacuum?

    1. A.Sound travels only at frequencies above radio waves
    2. B.Sound needs matter to transmit its vibrationsCorrect answer: B
    3. C.Sound consists of photons with too little energy
    4. D.Sound loses its wavelength outside Earth's magnetic field

    Explanation: The source states: "Sound waves cannot travel in the vacuum of space because there is no medium to transmit these mechanical waves." Mechanical sound requires a material medium, whereas radio waves are electromagnetic. Frequency, photon energy, and Earth's magnetic field do not supply a missing sound medium.

    Reference: Anatomy of an Electromagnetic Wave — What are Electromagnetic and Mechanical waves?