Atoms
What is an Atom?
What is the smallest thing you can
think of? A cell, a virus, or a speck
of dust? All of those things are
HUGE when you compare them to
an atom.
Atoms are the smallest unit of
matter.
Matter is anything that has mass
and takes up space.
A ball is matter, water is matter,
even the air you breathe is matter!
Atoms
How Big Are Atoms, Really?
Atoms are so small you can’t even see them
with most microscopes.
In fact, atoms are so small, there would be too
many to count in the Kiss you just divided! Take
a look at these examples:
A piece of paper is about 10,000 atoms thick.
Grains of Sand by Sean O’Flaherty. Retrieved from
Wikimedia Commons 6/13/09.
A single grain of sand has around 80 million,
million, million atoms in it! That is an 8 followed
by 19 zeros in one grain of sand!
And one drop of water has 2,000,000,000,
000,000,000,000 (that’s 2,000 billion, billion
atoms!)
Drop of Water by Tanya Puntii. Retrieved from Flickr
6/13/09.
Let’s cut some paper!
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Take a piece of paper and pair of
scissors.
Cut the paper in half.
Then cut one of the halves in half.
Then cut one of THOSE halves in half.
Then again …
And again …
Count your cuts … until you can’t cut it in
half anymore!
What do we have?
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How many times were we able to cut
the paper in half?
Is the paper as tiny as we can get it?
Is it still paper?
Is it the size of an atom?
Atoms
What Are Atoms Made of?
Atoms are the smallest piece of
matter that still look like and
behave like the original piece
of matter (just like the smallest
piece of paper you could cut
still looked like paper). But
atoms are made of even
smaller particles called
electrons, protons, and neutrons.
Atoms
The Atoms Family
Let’s look at the following story about
Matterville. Matterville is actually about an
atom. As you read the story you will learn
about the particles that make up an atom. In
the story the particles are referred to as the
inhabitants of Matterville: The Atoms Family.
The Atoms Family was created by Kathleen Crawford, 1994
Presentation developed by Tracy Trimpe, 2006, http://sciencespot.net/
The Atoms Family Story
In the center of Matterville, there is a
place called the Nucleus Arcade,
where two members of the Atoms
Family like to hang out. Perky
Patty Proton, like her sisters, is
quite large with a huge smile and
eyes that sparkle (+). Patty is always
happy and has a very positive
personality. Nerdy Nelda Neutron
is large like Patty, but she has a
boring, flat mouth and eyes with
zero expression (o). Her family is
very apathetic and neutral about
everything. Patty, Nelda, and their
sisters spend all their time at the
arcade.
Name:
Patty Proton
Description:
Positive
Favorite Activity:
Hanging out at the Nucleus Arcade
Name:
Nelda Neutron
Description:
Neutral
Favorite Activity:
Hanging out at the Nucleus Arcade
Around the Nucleus Arcade, you will
find a series of roadways that are used
by another member of the Atoms
Family, Enraged Elliott Electron. Elliott
races madly around the Arcade on his
bright red chrome-plated HarleyDavidson. He rides so fast that no one
can be sure where he is at any time.
Elliott is much smaller than Patty and
Nelda and he is always angry because
these bigger relatives will not let him in
the Arcade. He has a frown on his face,
eyes that are squinted with anger, and a
very negative (-) attitude.
Name:
Elliott Electron
Description:
Negative
Favorite Activity:
Racing around the arcade
The first energy street can only hold
only two Electron brothers. The second
energy street, called the Energy
Freeway, can hold 8 brothers. The third
energy street, called the Energy
Superhighway, can hold 18 of the
brothers.
Energy Superhighway
Can hold 18 electrons
Energy Freeway
Can hold 8
electrons
Energy Street
Can hold 2
electrons
Nucleus Arcade
Contains protons & neutrons
The morale of Matterville is stable as long as each negative Electron brother
is balanced out by one positive Proton sister. The number of residents in
Matterville depends on the Proton and Neutron families.
Challenge: What would happen to the morale of Matterville if one Elliott
Electron was kidnapped?
Challenge 2: What would happen to the morale of Matterville if one Elliott
Electron moved to Matterville?
Atoms
Atomic Structure
So now that you’ve been introduced to the
Atoms Family, let’s review the structure of
an atom.
Atoms are made of protons, electrons
and neutrons. Protons and neutrons are
found in the center of an atom in a clump
called the nucleus. Electrons float around
the nucleus on the “roadways”.
Protons have a positive (+) charge,
electrons have a negative (-) charge and
neutrons don’t have a charge.
Proton
Neutron
Electron
Atoms
Atom Models
Scientists like to make models of
atoms to help people understand
what they look like. However, the
models scientists make can’t really
show exactly what atoms look like
because atoms are made of
mostly empty space.
Another problem with modeling an
atom is that the parts of an atom
are always moving.
Atoms
Atom Models
If you made a model of an atom
with a nucleus the size of a pea, in
order to make the model
represent the actual size of an
atom, the pea would have to be
placed on the 50 yard line of a
football field, and the electrons
would be placed all the way
outside the stadium!
Let’s look at atoms!