Ch 4: Organizing the Elements
BSCS Inquiry Science
Name:
Period:
Date:
Lab: Exploring Rutherford’s Experiment
Wall / End of Table
Marble
1 m between marble and wall
Fire/roll marble
Front row marbles (3) spacing
15cm, 45cm, 75cm and 10cm
from the end of the table. Back
row marbles (2) 30cm, 60cm and
5cm from the end of the table.
Directions:
Today you are going to simulate Ernest Rutherford’s experiment that changed our
understanding of the Universe forever.
q Construct the set up that you see above using the table, a meter stick, and 6 marbles.
q You will be firing/rolling your marble at the wall 50 times counting how many times you:
o Strike one of the marbles and it bounces back (without hitting the end of the table)
o Miss ALL the marbles (without hitting any of the marbles first)
o Strike the marble and then continues forward
q You must roll/fire your marble from 1 m away with your eyes closed.
q Every time you strike/hit a marble make sure to reset them to the original position.
Lab Write-up
Question (What are you trying to find out?): Why did some of the marbles bounce back?
Make a Prediction (Of why some of the marbles bounce back.):
Data Table (Record your results on the data table below: use tally marks):
Trials
Missed ALL the marbles
Hit marble &
continued forward
Hit marble &
bounced back
1
2
Average
Class
Average
Percent
Revised: 10/30/15
Ch 4: Organizing the Elements
BSCS Inquiry Science
Graph:
Make a Claim (Make a statement of why some of the marbles bounce back.):
Giving Supporting Evidence (Scientific data that supports the claim):
Explain your Reasoning (A justification that connects the evidence to the claim):
Revised: 10/30/15
Ch 4: Organizing the Elements
BSCS Inquiry Science
Explain: Super Model
q 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?
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….
The marble you are Is like..
rolling/firing
Your Thumb
Is like..
The lines of marbles
Is like..
Each marble
Is like..
An Alpha Particle
Because…….
Because it shoots toward atoms in
gold foil
The space between Is like..
the marbles
# of times your
marble bounced
straight back after
hitting a marble
Is like..
# of times your
marble missed all
the marbles
Is like..
# of times your
marble hit one
marble and
continued forward
Is like..
Revised: 10/30/15
Ch 4: Organizing the Elements
BSCS Inquiry Science
4. Draw and label a simplified sketch of the Rutherford’s Experiment:
5. Explain how the experiment works in a simplified way:
6. Explain what the major ideas were behind Rutherford’s discovery:
Stop & Think Questions p.169
1. Why are models especially important to your understanding of the structure of atoms?
2. a. What does this arrangement represent?
Answer with a labeled sketch:
Revised: 10/30/15
Ch 4: Organizing the Elements
BSCS Inquiry Science
b. Approximately where would electrons be located
in your line of marbles model?
c. Why don’t positive alpha particles bounce back away from the negative electrons?
d. 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.
e. What does it mean when all of the marbles are the same height vs. different heights?
f.
How might the macroscopic properties of foil change if different-sized marbles were
used in the model?
Revised: 10/30/15