Name ________________________________________ Date______________________
Rutherford Scattering—Building the Model of the Atom
Initial set-up: Go to https://phet.colorado.edu/en/simulation/rutherford-scattering and click on the simulation to
launch. Then, click on “Rutherford Atom.”
Part A: Testing Gold and Other Elements
1.) In Rutherford’s experiment, he used radioactive Uranium, in addition to magnetic deflection, to create a source
of alpha particles.
2.) You will now test the interaction listed in the data table below of various atoms with these alpha particles with
varying levels of energy. You will observe the interactions of the alpha particles most clearly by checking the
“trace” box to better see the path of the particles. As you are describing, make sure to use terms like repulsion,
attraction and bending and to observe what the majority of the particles are doing.
Number of
Protons
Number of
Neutrons
Identity of metal
element
Alpha Particle Energy
Interactions of Particles
79
118
Gold
Min
79
118
Gold
Halfway
79
118
Gold
Max
20
20
Calcium
Min
20
20
Calcium
Halfway
20
20
Calcium
Max
Part B: Analysis
3.) Compare all of your trials:
a. What did the majority of the alpha particles do?
b. What charge must the alpha particle have based on it’s interactions with a positive nucleus? Explain how
you can tell.
