E
ParticLes
lements are the building blocks
small to see even with a microscope. But
of matter. On Earth there are 90
different elements. Carbon is one
element. Aluminum is another element.
they are still pieces of the element copper.
Gold is a third element. All of the elements
are different from one another. Each
element has its own unique properties.
What Are Elements
Made Of?
If you cut a copper wire in half, you have
two smaller copper wires. If you cut each
of those short wires in half, you have four
really short copper wires. If you cut those
in half, you have some little bits of copper
that don’t look like wire anymore. But
they are still pieces of the element copper.
A little pile of
copper dust
magnified millions
of times
If you keep cutting the copper bits in half,
you will finally end up with the smallest
possible piece of copper. The smallest
piece of copper is the copper particle. If
you cut the copper particle in half, it is no
longer copper.
Cu
One copper particle magnified billions
and billions of times
Particle is the word used to describe the
smallest piece of any substance that is still
Copper wire cut into small pieces is still
the element copper.
that substance. Every substance has its
own kind of particle. Copper is made of
copper particles. Aluminum is made of
aluminum particles. Gold is made of gold
particles. Each of the 90 elements is made
of its own kind of particle.
Imagine that you could cut one of those
bits of copper into a million tiny pieces.
Then cut one of those tiny pieces into a
billion pieces. The pieces would be too
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More Than 90 Particles
Remember, elements combine to make
new substances. Elements can combine in
millions of different ways to make millions
of different substances. Each different
substance has its own unique particle. So
there are millions of different kinds of
particles in the world.
Here is an example. Two hydrogen (H)
particles and one oxygen (O) particle can
combine. That forms the substance water.
The chemical formula for water is H2O.
The formula shows that the water particle
is made of two hydrogen particles and one
oxygen particle.
The elements hydrogen and
oxygen combine to form a
water particle.
Sodium bicarbonate is a substance. Like
all substances, it has a particle. The
chemical formula for sodium bicarbonate
shows which elements combine to make
a sodium bicarbonate particle. The
chemical formula for sodium bicarbonate
is NaHCO3. Which element particles
combine to make one sodium bicarbonate
particle? One sodium particle, one
hydrogen particle, one carbon particle, and
three oxygen particles.
The elements sodium,
carbon, oxygen, and
hydrogen combine
to form a sodium
bicarbonate particle.
All of the other substances you have
worked with have particles. The
sodium chloride particle (NaCl) is
small. Magnesium sulfate (MgSO4) is a
larger particle. And the sucrose particle
(C12H22O11) is the largest of the ones you
used.
Representing Particles
Particles of substances can be lots of
different shapes. Some particles are long
and thin. Some are bumpy. But even the
largest particles are far too small to see.
Even though particles are different sizes
and shapes, you can represent them as
little balls. You can draw the little balls in
different colors when you want to show
that particles of two or more substances are
present. Representing particles as balls of
different colors allows you to think about
how particles are organized in a substance
and what the particles are doing.
Review Questions
1. What is a particle?
2. What is the difference between an
element and a particle?
3. How many different kinds of
particles are there in the world?
Explain your answer.
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