Ch 4: Organizing the Elements
BSCS Inquiry Science
Name:
Period:
Date:
Lab: Exploring Rutherford’s Experiment
Book
1 m between marble and wall
Fire/roll marble
Marbles 12 cm
apart and 5 cm
in front of wall
Wall / End of Table
60 cm between books
Marble
Book
Directions:
Today you are going to simulate Ernest Rutherford’s experiment that changed our
understanding of the Universe forever.
 Construct the set up that you see above using 2 books, the wall, a ruler, and 5 marbles.
 You will be firing your marble at the wall 50 times Counting how many times you:
o
Strike one of the marbles and bounce back (without hitting the wall)
o
Strike the wall
o
Strike the marble and then the wall
 You must fire/roll your marble from 1 m away with your eyes closed.
 Every time you strike a wall marble make sure to reset them to the original position.
Lab Write-up
Question (What are you trying to find out?):
Hypothesis (What do you predict will happen and why):
Data Table (Create a data table to record your results):
HINT: record how many times the marble hits the; other marbles, marble then wall, just wall
Revised: 12/8/08
Ch 4: Organizing the Elements
BSCS Inquiry Science
Graph:
Conclusion:
Explain: Super Model
 Read pages 162-163 in your text.
Part I: The Rutherford Atom: A Conceptual Model (p.163)
1. Try to picture Rutherford’s Model of the atom by reading Ernest Rutherford (1871-1937) on
p.164-165.
2. Draw Rutherford’s “model” of the atom. Why did he believe it looked this way?
Revised: 12/8/08
Ch 4: Organizing the Elements
BSCS Inquiry Science
3. Complete the Table Below using your Marble Model, Figure 4.2 on page 164
Feature of your
marble model
Is like.. Piece of evidence from
Rutherford’s
Experiment….
Because…….
The marble you
are firing/rolling
Is like..
Because it shoots toward atoms in
gold foil
Your Thumb
Is like..
An Alpha Particle
The line of marbles Is like..
Each marble
Is like..
The space
between the
marbles
Is like..
# times your
marble bounced
straight back
Is like..
# of times you hit
the wall
Is like..
# of times the
marble hit the
marbles and then
the wall
Is like..
4. Draw and label a simplified sketch of the Rutherford’s Experiment:
Revised: 12/8/08
Ch 4: Organizing the Elements
BSCS Inquiry Science
5. Explain how the experiment works in a simplified way:
6. Explain what the major ideas were behind Rutherford’s discovery:
7. Read “What is a Model” on p.167: Define the following with words:
 Physical Model:
 Conceptual Model:
 Inference:
Stop & Think Questions p.169
1. What are some characteristics of a good & bad model?
Good
Bad
2. Why are models especially important to your understanding of the structure of atoms?
3. Think about what it would look like if you put all the marbles in lines one in front of the other
but slightly off set:
a. What does this new arrangement represent?
Answer with a labeled sketch:
Revised: 12/8/08
Ch 4: Organizing the Elements
BSCS Inquiry Science
b. Why is it easy for the marble to pass between the marbles of the original single line
marble model you built?
c. What does the new multi-layer model represent?
d. Approximately where would electrons be located in your line of marbles model?
e. Why don’t positive alpha particles bounce back away from the negative electrons?
f.
Why don’t the alpha particles hit and stick? Read the sidebar JJ Thomson on p.170 to
understand how surprisingly small the mass of an electron is.
g. What does it mean when all of the marbles are the same height?
h. How might the macroscopic properties of foil change if different-sized marbles were
used in the model?
Revised: 12/8/08