Unit 2 Chem test Flashcards
Democritus
Was not a scientist was a philosophist came up with idea of Atomos which means indevisable
Dalton
Experimented with dissolved gases the soild sphere theory or “billard ball theory”
Could not explain chemical bonding
Thomson
Investgated cathode rays using a cathode ray tube- came up with the plum pudding model
* Observations
* When electric charge applied CR bent
* Exp. stayed the
Rutherford
Worked with radiations came up with “the nuclear model”
- Observations
- Most Alpha particles passed straight through
- some particles were slightly deflected
- some partivles bounced back
- Conclusions
- most atoms are empty space
- there is something very small at center of atom
- most of the mass off the atom is in the nucelus
Model
A visual, verbal, or mathmatical explanation of things that are hard to visualize
Cathode Ray Tube
Thomsons way to discover that all atoms have electrons
Plum pudding model
JJ Thomsons all electrons embedded in “postivitly charged stuff”
Proton
- Location in Atom: Nueculus
- Charge: Postive
- Mass: 1AMU
Nuetron
- Location in atom: Nueculus
- Charge: nuetral
- Mass: 1 AMU
Electron
Location in Atom: Outside
Charge: Negetive
Mass: almost 0
Mass number
The number of protons and nuetrons in the nuceulus
Top number 12 over 10 C example
Atomic Number
Number of protons in nucleus- often equal to number of electrons in nuetral atom identifys an atom
bottom number
Ion
An atom with an electral charge
Isotope
Atoms with the same number of protons but different number of nuetrons
Reactants
The starting materials before undergoing a chemical change
