Download Atoms What is an Atom?

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!
What is an atom? (cont.)
What would we find if we were
to break down a material into
the parts that make it up (i.e.
microscopic structure)? For
example, if you were to take a
piece of pure gold, and cut in
half over and over again, you
would eventually get to the
smallest particle that still retains
the properties of gold. What
would this particle be called?
The answer lies within the atomthe smallest building block of
matter. Atoms make up each and
every object in our natural
world.
Terms to Know
o Atom
o Molecule
o Solid
o Liquid
o Gas
o Model
o Element
Atoms
Can You Divide a Kiss?
Complete the activity
described on the following
page to help you understand
more about atoms.
You will need a chocolate Kiss
(a chocolate chip, a cracker, or
a piece of bread would work
too), a napkin, and a butter
knife.
Atoms
Can You Divide A Kiss?
Procedure
1. Unwrap the Kiss and place it on
the napkin.
2. Use the butter knife to cut the Kiss
in half.
3. Cut each half into half again.
4. Continue to cut the Kiss in half
until you cut the smallest piece
you possibly can get.
5. Answer the Analysis Questions &
eat your Kiss!
Analysis Questions
1. Can you divide the Kiss forever?
Why or why not?
2. If you could keep dividing the
Kiss, what would its smallest piece
look like? Draw a picture and
write a description as if you were
looking at the piece through a
microscope.
3. In what ways would the smallest
piece be like the original Kiss? In
what ways would it be different?
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.
How big are atoms? (cont.)
The graphite in your pencil is composed of
the element carbon. Imagine taking a small
piece of carbon and grinding it until it is a
fine dust. Each speck of carbon would still
have
all of the physical and chemical properties
of the carbon atom. Now imagine that you
could somehow keep dividing the speck of
carbon into smaller and smaller pieces.
Eventually, you would reach a point where
your carbon sample is as small as it could
possibly be.
Figure 1. Images of individual
gold atoms can be seen on
the surface of a smooth sheet
of gold metal using scanning
tunneling microscopy.
How do scientists study something they
can’t see?
They make models.- a tool constructed
by the scientist based on all the known
experimental evidence about a
particular thing. Scientists work with
models because reality is complex and
difficult. An atom is an example of a
system that is both difficult and
complex. There are many parts inside
of an atom. It is useful to use a model
because it helps us understand what
cannot be seen with our own eyes.
Models are necessary in science.
However, you must always remember
that a model is only a representation of
the real thing.
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 Kiss you
could cut still looked like and tasted
like chocolate). But atoms are made
of even smaller particles called
electrons, protons, and neutrons.
Atoms
The Atoms Family
Read 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.
Atoms
The Atoms Family
In the center of Matterville, there is a
place called the Nucleus Arcade, where
two members of the Atoms Family like to
hang out. The first is Perky Patty Proton.
Like her sisters, she is quite large with a
huge smile and eyes that sparkle (+).
Patty is always happy and has a very
positive personality.
The second family member in the Nucleus
Arcade is Nerdy Nelda Neutron. She is
large like Patty, but 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 of 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
Atoms
The Atoms Family
Around the Nucleus Arcade, you will find a series of roadways, the Energy
Streets. These Energy Streets are used by another member of the Atoms
Family, Enraged Elliott Electron. Elliott races madly around the Nucleus
Arcade on his bright red chrome-plated Harley-Davidson. 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 Nucleus 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
Atoms
The Atoms Family
The first roadway, Energy Street can only hold two Electron brothers at the
same time. The second energy street, called the Energy Freeway, can
hold 8 Electron brothers. The third energy street, called the Energy
Superhighway, can hold 18 of the
Energy
Electron Brothers but is often
Superhighway
happy with 8.
Can hold 18
electrons
Energy
Freeway Can
hold 8
electrons
Nucleus Arcade
Contains protons &
neutrons
Energy Street
Can hold 2
electrons
Atoms
The Atoms Family
The morale of Matterville is stable as long as each negative Electron brother is
balanced out by one positive Proton sister. For example if there are 10 Elliott
Electrons there would need to be 10 Patty Protons.
What do you think would happen to the morale of Matterville if one Elliott Electron
was kidnapped and taken away from Matterville?
Atoms
The Atoms Family
Challenge 2: What would happen to the morale of Matterville if one Elliott Electron
moved to Matterville?
Atoms
The Atoms Family
1st Verse:
They’re tiny and they’re teeny,
Much smaller than a beany,
They never can be seeny,
The Atoms Family.
Chorus
3rd Verse:
Neutrons can be found,
Where protons hang around;
Electrons they surround
The Atoms Family.
Chorus
2nd Verse:
Together they make gases,
And liquids like molasses,
And all the solid masses,
The Atoms Family
Chorus
Chorus:
They are so small.
(Snap, snap)
They’re round like a ball.
(Snap, snap)
They make up the air.
They’re everywhere.
Can’t see them at all.
(Snap, snap)
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!
Watch Nova Science Now Atoms
http://www.pbs.org/wgbh/nova/physics
/atoms-electrons.html