Atomic Structure
What is the structure of an atom
and what is an isotope?
Starter: Complete the card sort on atoms and then use the
plastercine to make a model of what you think an atom looks
like.
Atomic Structure
What is the structure of an atom
and what is an isotope?
Starter: Complete the card sort on atoms and atomic
structure.
Learning Outcomes
• describe the Rutherford–Geiger–Marsden alpha
particle and gold foil scattering experiment
• explain that the results show the atom has a
small, massive, positively charged nucleus
• explain that the nuclear model was thought up
creatively to account for the data
Atomic structure
Atomic structure
Atomic Information
Pick 1 element and work out the number of
protons
Neutrons
Electrons
Task: complete the worksheet
filling in the data.
How do we know all this info?
• Rutherford–Geiger–Marsden alpha
particle and gold foil scattering experiment
gave us the clues and they used the data
to produce a model of an atom.
Check point
• Which 2 parts of the atom are found in the
nucleus ?
1
Electron and
neutron
2
Electron and
Proton
3
Proton and
neutron
Lets investigate
• Try the scatter experiment.
The equipment
Structure of an Atom- Evidence for
Rutherford fired positively charged
particles at thin gold foil
Au Au
Au Au
Nearly all went
straight through
Some were
deflected
Au Au
Au Au
Some bounced
back
DISCUSS :
Can you explain how the
experiment proves this model of
an atom?
ELECTRONS
PROTONS
NEUTRONS
The observations
Why have these deflections been observed?
Conclusions
Evidence
Most alpha particles
went straight through
A few were deflected at
small angles (90)
Very few (1 in 10,000)
were deflected at large
angles (>90)
Conclusion
Plenary
• Describe an atom as clearly and concisely
as possible, in 2 sentences.
•
•
•
•
•
Proton
Neutron
Electron
Nucleus
Charge
Complete the GCSE question