Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
7 Cards in this Set
- Front
- Back
|
John Dalton
|
PROPOSED ATOMIC THEORY 1808
+ atoms were a tiny hard sphere |
|
|
Joseph John Thomson
|
1868 - made observations with cathode ray tube. identified the electron. said that the nucleus has electrons embedded in it to give charge. cookie dough model.
|
|
|
Ernest Rutherford
|
1911 - gold foil experiment. deferred that atoms made of mostly empty space. positively charged nucleus electrons surrounded nucleus. said that nucleus held majority of mass.
|
|
|
Niels Bohr
|
1885-1962 - said that the electons moved around the nucleus in fixed orbits with a fixed amount of energy.
|
|
|
ATOMIC THEORY
proposed by whom? who gathered evidence for it? what year did he publish it? |
ppd by greeks in 400 BC
John Dalton collected evidence published it in 1808 |
|
|
ATOMIC THEORY
pts one through three |
1. all elements are composed of extremely small particles (atoms)
2. all atoms of a given element are identical. 3. atoms of different elements have different properties |
|
|
ATOMIC THEORY
pts 4 through six |
4. atoms are only rearranged in chemical reactions, not changed
5. compounds are formed when atoms of one or more elements combine 6. a compound is defined by the number type and proportion of the constituent atoms |
