Atomic Theory Flashcards
Democritus
- Everything composed of atoms that are physically indivisible
- Always moving
Dalton
- Combines info to make sphere model
- Atoms can’t be created/destroyed
Thomson
- Discovered e
- Pudding model
Rutherford
Nucleus w/protons, neutrons
Bohr
- NRG lvls
- Quantum levels
Orbits
Circles around nucleus
Quanta
Unit/packet of NRG
Schrodinger Wave eqn
e is circular standing wave around nucleus
Orbital
Probable area around nucleus e is found
Heisenberg’s uncertainty principle
Impossible to know exact position and speed of e
Quantum Mechanical Model
- e can be in diff orbitals from quantas of nrg
- e is a probability distribution
Quantum Numbers
Desc quantum mechanical properties of orbitals
Principal quantum number
- n
- desc size, nrg of orbital
- each orbital gets larger, not equally spaced
Secondary quantum number
- l
- subshells
- desc shape of atomic orbital
- 0 to n - 1
s
- n = 1
- l = 0
- sharp
p
- n = 2
- l = 1
- principal
d
- n = 3
- l = 2
- diffuse
f
- n = 4
- l = 3
- fundamental
Magnetic quantum number
- ml
- desc oritentation of atomic orbitals relative to other orbitals
- -l, 0, +l
Nodes
areas of 0 probability of e-
s orbitals shape
Spherical shapes
p orbitals shape
- Lobes separated by nodes at nucleus
- multiple axis
d orbitals
- 4 lobes around the centre
- 5th has two lobes + donuts
Spin quantum number
- ms
- +1/2, - 1/2
- 1 spins up, 1 spins down
Pauli exclusion principle
No 2 e in same atom can have same quantum #
Aufbau Principle
e are added to lowest orbitals first
Hund’s Rule
- e are distributed equally in orbitals
- no pairing happens until all spots are full
Valence of Metals are dependent on
s and d values
Valence of Nonmetals are dependent on
s and p values
