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fossil fuel
the preserved remains of
plants and animals that lived long ago
and changed into oil, coal, and natural
gas
freeze
to change from a liquid to a solid
state as a result of cooling
freezing point (0°C)
the temperature at
which water becomes a solid (ice)
fresh water
water that is in lakes, rivers,
groundwater, soil, and the atmosphere
gas
a state of matter with no definite
shape or volume; usually invisible
glacier
a large mass of ice moving slowly
over land
gram (g)
the basic unit of mass in the
metric system
gravity
the natural force that pulls
objects toward each other. On Earth, all
objects are pulled toward the center of
Earth because of gravity.
groundwater
water found in the spaces
between rock particles (sand, gravel,
pebbles), and in cracks in solid rock
heat
observable evidence of energy
humidity
water vapor in the air
humus (HEW-mus)
bits of dead plant
and animal parts in the soil
hurricane
a severe tropical storm that
produces high winds
ice
the solid state of water
iceberg
a large mass of ice that has
broken from a glacier and floats in the
ocean
liquid
a state of matter with no definite
shape but a definite volume
Liter (L)
the basic unit of liquid volume
in the metric system
mass
the amount of material in
something
matter
anything that has mass and takes
up space
measure
to compare the size, capacity,
or mass of an object to a known object or
known system
melt
to change from a solid to a liquid
state as a result of warming
meteorologist
a scientist who studies
the weather
mixture
two or more substances together
more dense
when an object has more
mass for its size than another object.
When an object sinks in water, it is more
dense than water.
natural resource
a material such as
soil or water that comes from the natural
environment
nonrenewable resource
a natural
resource that cannot be replaced if it is
used up
opinion
a claim based on belief, not on
scientific data or observations
perpetual renewable resource
a
renewable resource that lasts forever
polar zone
a very cold climate with long
winters (North and South Poles)
precipitation
rain, snow, sleet, or hail
that falls to the ground
predict
to estimate a future event based
on data or experience
property
something that you can
observe about an object or a material
rain
liquid water that is condensed from
water vapor in the atmosphere and falls to
Earth in drops
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