1. 3-2: Discovering Atomic Structure
By Ms. Pacheco

2. Michael Faraday 1839 (English)
Faraday suggested that atoms of different elements behave differently due to electricity, though he didn’t know exactly how
He was right; atoms contain particles that have an electric charge

3. Ben Franklin Faraday wasn’t the first to study electricity, though
Franklin was a statesman and a scientist
Famous for his kite and key experiment
Said that objects had either a positive or negative charge
Like charges repel; opposite charges attract

4. A statue of Franklin at the University of Philadelphia

6. Franklin was also… An inventor A printer A philosopher A musician
An economist
The only person to sign
The Declaration of Independence
The Treaty and Alliance of France
The Treaty of Paris
The Constitution

7. One last note on Franklin…
He loved turkeys
He even used them in his experiments with electricity!!!!!
He actually wanted the national bird to be a turkey!

8. Ben Franklin On The Turkey As National Bird
"For my own part I wish the Bald Eagle had not been chosen the Representative of our Country. He is a Bird of bad moral Character. He does not get his Living honestly. You may have seen him perched on some dead Tree near the River, where, too lazy to fish for himself, he watches the Labour of the Fishing Hawk; and when that diligent Bird has at length taken a Fish, and is bearing it to his Nest for the Support of his Mate and young Ones, the Bald Eagle pursues him and takes it from him.
"With all this Injustice, he is never in good Case but like those among Men who live by Sharping & Robbing he is generally poor and often very lousy. Besides he is a rank Coward: The little King Bird not bigger than a Sparrow attacks him boldly and drives him out of the District. He is therefore by no means a proper Emblem for the brave and honest Cincinnati of America who have driven all the King birds from our Country....
"I am on this account not displeased that the Figure is not known as a Bald Eagle, but looks more like a Turkey. For the Truth the Turkey is in Comparison a much more respectable Bird, and withal a true original Native of America... He is besides, though a little vain & silly, a Bird of Courage, and would not hesitate to attack a Grenadier of the British Guards who should presume to invade his Farm Yard with a red Coat on."
--Benjamin Franklin, in a letter to his daughter

9. Can you imagine?!?

10. J.J. Thomson 1896 (English scientist)
Using cathode ray tubes, discovered that atoms contained a negatively charged particle that he will call the electron

12. Robert Millikan
1909 (American physicist)
Using an oil drop experiment, calculated the charge and mass of a single electron

13. Henri Becquerel 1896 (French physicist)
Accidentally discovered radioactivity (the emission of radiation from an element)

14. Becquerel’s First Radiograph

15. Becquerel’s worked with and shared the 1903 Nobel Prize in Physics with…
Pierre and Marie Curie
Both would later die from exposure to radiation

16. Ernest Rutherford 1909 (New Zealand scientist)
Performed an alpha scattering experiment, using gold foil

17. Ernest Rutherford
Proved the existence of a positively changed particle in an atom, that he called a proton
Said that the core of the atom (he called the nucleus) contains all of the mass and all of the positive charge

18. Niels Bohr
Danish (1913):
electrons travel around the nucleus in orbits (sun-planet model)
Electrons could drop from higher energy level to a lower energy level, emitting

19. First X-ray (1896)