The Atom Flashcards
Law of constant composition
a compound always contains atoms of two or more elements combined in definitw porportions of mass and composition
Law of multiple prportions
atoms with 2 or more elements that may combine in differnt ratios
ex: NO, NO2, N2O
Daltons atomic theory
- indivisible and indestructible particles
- atoms of same elements have same masses
- atoms of different elements have different masses
- atoms combine in whole number ratios
Objections to Daltons theory
- atoms are not indivisible– subatomic particles
- not all atoms of same elements have same masses– isoptopes
JJ Thompson
- Cathode Ray:electron
- plum pudding : electrons are scattered unevenly and surrounded by positive charge to balance negative
- established presence of proton
Oil Drop Experiment
- Milikan
- by varying charges on plates, found that he could suspend the drops of oil
Proton
- e goldstein
Ernest Rutherford
- Gold foil
- concluded that atoms have empty space and a nucleus
Subatomic Particles
- neutrons
Niels Bohr
- bohr model
- electrons move in definite orbitals around the nucleus
Particle Wave Dulaity
-Einstein
-
Uncertainity Pribicple
- Heisenbrg
- impossible to know the location and momentum of an electron and the best that can be done is finding the probability
Edwin Schoedinger
- propsed electrons are waves
Aufbau Principle
lowest energy possible
Pauli exclusion principle
want space to minimize repulsion (2 electrons per orbital)
