Unit 3 Test Flashcards
(14 cards)
1
Q
John Dalton
A
- Atom was an indivisible hard sphere
- Billiard ball model where the atom was an indivisible hard sphere
2
Q
J.J. Thompson
A
- Discovered electrons
- Cathode Ray Tube experiment
- Plum pudding model
3
Q
Ernest Rutherford
A
- Gold Foil experiment
- Discovered the nucleus: small, dense, positively charged, and the rest of the atom was largely empty space
4
Q
James Chadwick
A
- Discovered neutrons and isotopes
5
Q
Niel Bohr
A
- Planetary model
- Electrons have different energy levels
6
Q
Modern Theory
A
Electron Cloud
7
Q
Atomic Number
A
Number of protons & electrons but electrons can differ if it’s isotopic
8
Q
Atomic Mass Number
A
Protons + Neutrons
9
Q
Neutrons
A
Mass number - atomic number
10
Q
Average atomic mass
A
Mass of isotope 1 x % (relative abundance) +
Mass of isotope 2 x % (relative abundance) +
11
Q
Isotopic notation
A
23
Na
11
12
Q
Hund’s Rule
A
- Every orbital in a sublevel is singly occupied before doubly so
- All electrons in singly occupied orbitals have the same spin
13
Q
Aufbau Principle
A
- Electrons occupy orbitals of the lowest energy first
14
Q
Pauli Exclusion Principle
A
- Any orbital at most can occupy two electrons of opposite spins
