1. Starter A. Planetary or Nuclear Model B. Electron Cloud Model
Write the letter of the correct model next to the experiment/evidence used to develop the models.
A. Planetary or Nuclear
Model
B. Electron Cloud Model
C. Plum Pudding Model
Experiments with cathode ray tubes led to the discovery of charged particles termed “electrons”
The gold foil experiment demonstrated that atoms have a dense center of positive charge around which tiny electrons move in a space that is otherwise empty
Experiments with electron diffraction and equations showed that electrons have properties of both waves and particles

2. Starter
Write the letter of the correct model next to the experiment/evidence used to develop the models.
Planetary or Nuclear Model
Electron Cloud Model
Plum Pudding Model
Experiments with cathode ray tubes led to the discovery of charged particles termed “electrons”
The gold foil experiment demonstrated that atoms have a dense center of positive charge around which tiny electrons move in a space that is otherwise empty
Experiments with electron diffraction and equations showed that electrons have properties of both waves and particles C A B

3. I can evaluate the limitations of using models to describe atoms.
Objective 1
I can evaluate the limitations of using models to describe atoms.

4. Democritus
He proposed that matter could not be divided into smaller pieces forever. He claimed that matter was made of small, hard particles, that he called “atomos”.
Strengths?
Weaknesses?

5. John Dalton
John Dalton stated all elements are composed of atoms. Dalton viewed atoms as tiny, solid ball.
Strengths?
Weaknesses?

6. J. J. Thomson
Thomson theorized that the positive material in the atom must form something like the “batter” in a plum pudding, while the negative electrons must be scattered through this “batter”.
Strengths?
Weaknesses?

7. Ernest Rutherford
Rutherford suggested that the electrons were circling or “orbiting” the positively charged nucleus. This model is call the Planetary or Nuclear Model.
Strengths?
Weaknesses?

8. Niels Bohr
Niels Bohr proposed that electrons move around the nucleus in specific layers, or shells. Every atom has a specific number of electron shells.
Strengths?
Weaknesses?

9. Quantum Mechanical Model
The quantum mechanical model, the electrons are found in an electron Cloud. The electrons move around the nucleus in a cloud. The electrons do not have a fixed location or orbit.
Strengths?
Weaknesses?

10. Protons, Neutrons, & Electrons
Atomic Structure

11. I can evaluate the limitations of using models to describe atoms.
Objective 1
I can evaluate the limitations of using models to describe atoms.

12. Objective 2
I know the size, charge, and position of protons, neutrons, and electrons in an atom.

13. Using Models to Describe Atoms
Scientific Model: simple representation of a more complex system

14. Using Models to Describe Atoms
Strengths
can demonstrate a single attribute of the desired concept
can represent things too large or too small to normally demonstrate

15. Using Models to Describe Atoms
Limitation
cannot be made to scale
do not behave like the real object

16. Subatomic Particles - Position
Proton
Inside nucleus
Neutron
Electron
Outside nucleus

17. Subatomic Particles - Charge
A neutral atom must have one electron for every proton
Proton
Positive Charge
Neutron
Has no charge
Neither attracted nor repelled from other objects – they don’t interact with protons or electrons
Electron
Outside nucleus
The negative charge on the electron perfectly balances the positive charge on the proton

18. Subatomic Particles - Size
Proton
Has similar mass as a neutron
Neutron
Has similar mass as a proton but is slightly larger
Electron
Have extremely small mass compared to protons and neutrons
It would take about 1,830 electrons to equal the mass of one proton

19. Subatomic Particles - size
If Dr. Doofenshmirtz (of "Phineas and Ferb") invented an "atomic grow-i-nator" that made a proton the size of a BB, it would generate an atom the size of an NFL football stadium.

20. Basic atomic structure
nucleus
electrons
neutrons
electron cloud
protons
energy levels

21. Element Squares Atomic number Atomic Symbol Atomic name
Atomic mass/weight in atomic mass units (amu)

22. Atomic Number
Atomic number is equal to the number of protons in an atom
A neutral atom must have one electron for every proton
The number of neutrons can vary depending on the atomic mass. The number of neutrons may or may not be equal to the number of protons and electrons.

23. Objective 2
I can discriminate between the relative size, charge, and position of protons, neutrons, and electrons in an atom.