Science Test #6 Learning Outcomes
Unit 6, Lesson 3
Name: _______________________________
Test Date: _____________________________
Students need to learn and understand the meaning of the following vocabulary words AND
be able to apply them to a variety of situations.
1. hydrosphere- Earth’s water, whether found on continents or in oceans, including the
freshwater in ice, lakes, rivers, and underground
2. reservoir – a storage area for freshwater; a lake made by people (often created with a
dam) that collects and stores water until it is needed
3. aquifer – an underground layer of rock or soil filled with water
4. atmosphere- the layers of gases that surround Earth
5. air pressure – the force put on a given area by the weight of the air above it
6. mantle- a nearly melted layer of hot rock below Earth’s crust
7. lithosphere- the crust and the rigid part of Earth’s mantle
8. troposphere- the atmospheric layer of gases that is closest to earth’s surface; most
weather occurs in this layer; temperatures in the troposphere decrease with height
9. stratosphere- the layer of atmosphere that contains ozone and is located above the
troposphere; temperatures in the stratosphere increase with height
10. mesosphere- the coldest layer of the atmosphere; it is above the stratosphere; air
temperature decreases again with height in this layer
11. thermosphere- hot, outermost layer of the atmosphere; temperature increases quickly in
this layer with height
Students will learn in class about the following topics. Be prepared to be assessed on them.
1. Water covers about 75% of Earth’s surface. Most of it is found in the oceans. Water
can be found as a solid, liquid, or a gas (three states of matter). It can be found as a
solid in the form of ice or snow; as a liquid in oceans, lakes, rivers, etc.; and as a gas
in the atmosphere as water vapor.
2. How would you classify Earth’s water according to its motion?
Ice in glaciers moves slowly compared with liquid water and water vapor;
oceans and rivers move quickly and for great distances; ponds and lakes are often in
small basins and do not move much.
3. How is ocean water different from pond water and lake water? Ocean water is salty;
pond water and lake water usually are not.
4. Earth’s water exists in two basic forms: saltwater and freshwater. Freshwater contains
little or no salt. It comes from sources such as rivers, lakes, and also rainfall. Most of
Earth’s freshwater exists as ice. The Mississippi River is a major source of freshwater.
Most of the water on Earth is saltwater (97% because of oceans). 2.3% is freshwater
frozen at or near the North and South poles. Another 0.6% is liquid freshwater and
0.1% is water vapor in the air.
5. Scientists use the term salinity to describe how much salt is dissolved in water.
6. Glaciers are large sheets of ice that slowly move. Glaciers are part of Earth’s
hydrosphere.
7. Why is water on Earth’s surface found sometimes as a solid and sometimes as a liquid?
Temperature differences due to elevation and latitude determine water’s
state.
8. How is underground water, or groundwater, obtained for use? Wells are dug and water
is pumped out.
9. What are some reasons why one area of an ocean might be more salty than another?
Areas of the ocean that are near salty runoff from rocks and sand or near salt
deposits might have higher concentrations of salt. Underwater volcanoes may add to
the salt in some areas of the ocean.
10. What is the atmosphere made of? Most of the atmosphere is made of nitrogen gas
(78%) and oxygen (21%). The atmosphere also contains carbon dioxide, other
important gases, and water vapor (1%).
11. Know the 4 layers of the atmosphere (p. 325). The troposphere is the thinnest layer
and the thermosphere is the thickest layer. All of Earth’s life exists in the
troposphere. The troposphere contains about 80% of the total amount of air in the
atmosphere. Airplanes normally fly in the stratosphere because it is very stable. The
stratosphere contains the ozone layer which absorbs harmful rays from the Sun.
The thermosphere is where space shuttles orbit.
12. Earth is made of layers. Know the diagram of the Earth’s layers on p. 326 of your
text (crust, mantle, outer core, and inner core).
13. Earth’s solid rocky surface is the crust. The crust varies in thickness and includes the
continents and the ocean floor. The crust is thickest at the continents and thinnest at the
ocean floor. The layer beneath the crust is the mantle. Upper part of the mantle is solid
and rigid, or stiff. The crust and the rigid part of the mantle make up the lithosphere.
The part of the mantle below the lithosphere is very hot and flows very slowly (like
plastic putty). Beneath the mantle is the core- which has 2 parts. The outer core is the
molten (or liquid fluid) part of the core. The inner core is solid. Earth’s core is
extremely dense and is under high pressure.
14. What part of Earth is solid but still moves and flows slowly? A layer of the mantle just
below the outermost rigid part.
15. Which parts of the planet are mostly solid? The crust, the upper mantle, and the inner
core Which part of the planet is liquid? The outer core
16. What conditions might make travel to the center of the Earth difficult? High pressure;
high temperature; no light; no food or air