Chapter 3- Greeks Flashcards
Why were daltons ideas about atoms considered a scientific theory and the Greeks ideas were not
Dalton preformed experiments unlike the Greeks
Why did john dalton propose the atomic theory
To explain the 3 laws
Which statement in daltons atomic theory imply that an atom of gold is exactly the same as any other gold atom
All atoms of the same element are alike
What did john daltons atom look like
Solid sphere
When scientists discovered that atoms are composed of smaller particles why didn’t they reject the theory
Atoms are divisible into small particles
Aspects of daltons theory that have been proven wrong
- Atoms cannot be created, subdivided, or destroyed
- All atoms of the small element are the same, atoms of different elements are different
- Atoms are divisible into smaller particles
What happens when a positive and a negative charge come close
They attract
What happens when two positive charges come close
They repel
Why could JJ Thompson conclude that electrons are part of all atoms
He Tested the cathode ray tube with gases and metals and other elements
Two questions that remained unanswered
- What other particles made up the mass of an atom
2. Where is the positive charge?
Who was able to determine the actual mass of the electron? What was his experiment
RA Milikan with the oil drop experiment
Name of subatomic particle Thomson discovered
Electron
How did Thomsons discovery modify daltons
Dalton said atoms are indivisible, but atoms do have smaller particles
What other conclusions did Thomson make
- There had to be a positive charge to balance out the negative
- There had to be more mass somewhere
Alpha particle
Small, dense, heavy, positive charge
