Chapter 4 – Earth’s Water
Study Guide
Main Ideas
Lesson 1 – Earth: The Blue Planet
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Almost three-fourths of Earth’s surface is covered by water. Most of
the water on Earth is salt water.
Flowing water, waves pounding on shores, and volcanoes under the
ocean add salt to the ocean.
Most of the fresh water on Earth is frozen in ice sheets.
Lesson 2 – The Water Cycle
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Condensation occurs when a gas changes into a liquid.
Evaporation occurs when water changes from a liquid to a gas.
Precipitation falls as rain, sleet, hail, or snow.
Water changes form and moves from place to place in the water
cycle.
Lesson 3 – Fresh Water Resources
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Usable fresh water comes from running water, standing water, and
groundwater.
Fresh water from rain runs through watersheds. Plants, buildings,
and roads all affect this flow.
Fresh water can be polluted by human activities. It is protected by
government laws and cleaned in water treatment plants.
Lesson 4 – California’s Water Supply
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Most of California’s precipitation falls in the north.
A system of aqueducts, reservoirs, and dams helps to supply dry
areas of California with water.
Water conservation can help Californians meet their needs for fresh
water.
The Scientific Method
Observation → Question → Hypothesis → Experiment → Conclusion
Outlines
* For more detailed information, refer to your lesson outlines.
Vocabulary
Word
Definition
aqueduct
A channel built by people to move water
from one place to another.
aquifer
An underground layer of rock or soil that is
capable of absorbing water.
condensation
The process of water vapor changing to
liquid water.
conservation
The act of saving or protecting something.
contaminate
To make dirty; to pollute.
dam
A barrier that prevents water from flowing.
drought
A long period of dry weather.
evaporation
The process of liquid changing into a gas.
Picture
filtration
The process that helps make polluted water
drinkable.
fresh water
Water that contains little or no dissolved salt.
glacier
A large body of ice that moves slowly over
land.
lake
A body of fresh water.
liquid
State of matter that has a definite volume
but not a definite shape.
Mono Lake
A saltwater lake in California.
ocean
A large body of salt water.
pollute
To make dirty; to contaminate.
precipitation
Water that falls from the air to the ground as
rain, sleet, hail, or snow.
reclamation
To recycle or to make usable again.
reservoir
A man-made lake that is used to store
water.
river
Running water that contains a very small
amount of salt.
solid
State of matter that has a definite shape and
volume.
salt water
Water that contains salt.
watershed
An area of land that drains into a river.
water cycle
The continuous movement of water as it
changes from liquid to gas (evaporation),
gas to liquid (condensation), and then falls
to the ground (precipitation).
water vapor
The gas state of water.