1.  Warm-Up: Atom Probe  Classwork: Atom notes; Create a Timeline  Homework: The Atoms Family Album (Glue In)

2.  All matter is composed of particles called atoms.  small,  fast movingCombination of thousands of individual theories that provide evidence

3.  Scientists rely upon models to help us to understand the atom. Believe it or not this is a microscope.

4.  May not always look like the actual object  Attempts to use familiar ideas to describe unfamiliar things in a visual way. This is a painting of a young woman by Pablo Picasso. Does it actually look like a young woman?

5. The model above represents the most modern version of the atom. Many of the models that you have seen may look like the one below. It shows the parts and structure of the atom.

6.  Gathered without being able to directly observe the object.  Each new bit of information gives us a better understanding of atoms.

7.  As new information is collected.  From the early Greek concept to the modern atomic theory, scientists have built upon and modified existing models of the atom.  Today, you will make a visual representation of these changes over time ….

9.  Who: Aristotle, Democritus  When: More than 2000 years ago  Where: Greece  What: Aristotle believed in 4 elements: Earth, Air, Fire, and Water. Democritus believed that matter was made of small particles he named “atoms”.  Why: Observation and inference explains the existence of everything.

10. Aristotle Democritus

11.  Who: European Scientists  When: 800 – 900 years ago  Where: Europe  What: Their work developed into what is now modern chemistry.  Why: Trying to change ordinary materials into gold.

12. Alchemic Symbols

13.  Who: John Dalton  When: 1808  Where: England  What: Described atoms as tiny particles that could not be divided. Thought each element was made of its own kind of atom.  Why: Building on the ideas of Democritus in ancient Greece.

14. John Dalton

15.  Who: J. J. Thompson  When: 1897  Where: England  What: Thompson discovered that electrons were smaller particles of an atom and were negatively charged.  Why: Thought an atom was like a jigsaw puzzle made of smaller pieces.  Future: Thompson knew atoms were neutrally charged, but couldn’t find the positive particle.

16. J. J. Thompson

17.  Who: Ernest Rutherford  When: 1911  Where: England  What: Conducted an experiment to isolate the positive particles in an atom.  Why: Theorized that the atoms were mostly empty space, but had a dense central core.  Future: He knew that atoms had positive and negative particles, but could not decide how they were arranged.

18. Ernest Rutherford

19. WWho: Niels Bohr WWhen: 1913 WWhere: England WWhat: Proposed that electrons traveled in fixed paths around the nucleus. WWhy: Bohr was trying to show why the negative electrons were not sucked into the nucleus of the atom. FFuture: Scientists still use the Bohr model to show the number of electrons in each orbit.

20. Niels Bohr

21. WWho: James Chadwick WWhen: 1932 WWhere: England WWhat: Proposed that since electrons have almost no mass, something besides the protons in the nucleus were adding to the mass. WWhy: Chadwick was trying to show a neutral particle -- one with the same mass as a proton, but with zero charge. He called this particle a neutron. FFuture: The discovery of the neutron led to discoveries relating to splitting an atom.

23.  Who: Schrödinger, Born, Heisenberg  When: 1920’s  Where: Austria, German  What: Electrons travel around the nucleus in random orbits. Electrons travel so fast, they appear to form a “cloud” around the nucleus.  Why: No experiment can measure the position and momentum of an electron so mathematics and physics make models.

24.  Must include a title.  Must have accurate time intervals.  Must include a spot for each of the 8 items.  Must include a brief description of the model (in your own words!!!).  Must have a picture of the model (color is preferred) for each item.  Must be completed by the end of class.  Must have rubric attached to the back with names.