Earth & Space Science (Grade 6) Midterm — Semester 2, Form B

Part 1: Multiple Choice

1. Which gas in the atmosphere traps heat and adds to the greenhouse effect?
   1. A. Carbon dioxide
   2. B. Oxygen
   3. C. Argon
   4. D. Nitrogen
2. What is the main cause of wind?
   1. A. The pull of the Moon
   2. B. Earthquakes on the sea floor
   3. C. Uneven heating of Earth's surface
   4. D. Earth's magnetic field
3. Which gas makes up the largest part of Earth's atmosphere?
   1. A. Oxygen
   2. B. Carbon dioxide
   3. C. Argon
   4. D. Nitrogen
4. Which instrument measures air pressure?
   1. A. Rain gauge
   2. B. Anemometer
   3. C. Thermometer
   4. D. Barometer
5. In which layer of the atmosphere does almost all weather happen?
   1. A. Thermosphere
   2. B. Stratosphere
   3. C. Mesosphere
   4. D. Troposphere
6. Where is most of Earth's fresh water stored?
   1. A. In rivers
   2. B. In the atmosphere
   3. C. In glaciers and ice caps
   4. D. In lakes
7. How do clouds form?
   1. A. Water droplets evaporate in warm air
   2. B. Water vapor cools and condenses into droplets
   3. C. Wind blows ocean water upward
   4. D. Rain rises back into the sky
8. Why is ocean water salty?
   1. A. Rain falling on the ocean is salty
   2. B. Sea plants produce salt
   3. C. Melting icebergs add salt
   4. D. Rivers carry dissolved minerals from rocks into the sea
9. When liquid water changes into water vapor, what is the process called?
   1. A. Condensation
   2. B. Precipitation
   3. C. Evaporation
   4. D. Runoff
10. Where is most of Earth's water found?
    1. A. Underground
    2. B. In glaciers and ice caps
    3. C. In the oceans
    4. D. In lakes and rivers
11. What causes day and night on Earth?
    1. A. Earth revolving around the Sun
    2. B. The Sun moving around Earth
    3. C. The Moon orbiting Earth
    4. D. Earth rotating on its axis
12. Which planet is closest to the Sun?
    1. A. Mars
    2. B. Venus
    3. C. Mercury
    4. D. Earth
13. A light-year is a unit used to measure what?
    1. A. Time
    2. B. Mass
    3. C. Brightness
    4. D. Distance
14. Which planet has the hottest average surface temperature?
    1. A. Venus
    2. B. Mars
    3. C. Mercury
    4. D. Jupiter
15. In 2006, astronomers reclassified Pluto. What is it now called?
    1. A. A moon
    2. B. An asteroid
    3. C. A dwarf planet
    4. D. A comet

Part 2: Written Response

16. Trace a single drop of water through the water cycle, from the ocean back to the ocean. Name each process and identify the energy source that drives it.