battery
a device that
makes a small amount of
electricity when it is
connected in a circuit.
calcium
a chemical
substance. Chalk,
eggshell, bones, and
teeth are just some
of the things that
contain calcium.
calcium carbonate
a
substance formed when
calcium combines with
carbon and oxygen.
carbon
a chemical
substance that is found in
all plants and animals.
carbon dioxide
a gas
that consists of carbon
combined with oxygen.
circuit
a complete path.
Electricity can flow only
when it has an unbroken
path, or circuit, to flow
around.
copper
a metal.
G
l
o
s
s
a
r
y
copper oxide
a mixture
of the metal copper and
the gas oxygen.
dissolve
to mix a solid
with a liquid by breaking
it up into tiny particles
that are too small to see.
electrode
a piece of
metal around which
chemicals collect,
producing electricity.
embryo
a tiny plant in
a seed before it begins
to grow.
evaporate
to change
from a liquid into a gas.
evergreen
having green
leaves all year round.
Evergreen shrubs and
trees lose their leaves
gradually during the year.
neutralize
to change so
that a liquid is neither
acid nor alkali.
nutrients
substances in
soil that help plants grow.
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