Atomic Structure Flashcards
1
Q
Early Greek Model (400 BC)
A
- Democritus
- Matter cannot be continuously subdivided
- Used the term “Atomos” (indivisible)
- The model became unpopular when Plato, Aristotle, and Socrates disagreed
2
Q
Dalton’s Model
A
- Matter is composed of tiny particles called atoms.
- Atoms are indestructible and indivisible.
- Atoms of the same element are identical in size, mass, and properties.
- Atoms of different elements can combine into compounds.
3
Q
Thomsons Plum Pudding Model
A
- Used a cathode ray tube for experiments
- Discovered electrons
- Said the atom was neutral due to a positive jelly-like sphere around the electrons
4
Q
Rutherfords Model
A
- Dense, positively charged center of the atom
- Atom is mostly empty space
5
Q
Bohr’s Planetary Model
A
- Electron orbit the nucleus in energy levels
- energy level n = 1 is closest to the nucleus
- Electrons gain energy to become excited and lose to produce light spectra
6
Q
Heisenberg / Schrodinger Model
A
- Current model
- Wave mechanical / Cloud Model
- impossible to know the exact location of an electron
- Atom = neutral
- Protons + Neutrons = Nucleus
- Orbitals propose the probable location of e-
7
Q
Proton
A
Positively charged particle
8
Q
Neutron
A
No Charge
9
Q
Electron
A
Negatively charged particle
10
Q
The # of protons is called?
A
The atomic number
11
Q
Where are protons and neutrons located?
A
The nucleus
12
Q
Why do we need neutrons?
A
Without them, the protons would repel from each other
13
Q
How to find the # of neutrons
A
mass # - atomic #
14
Q
Nucleons
A
particles that reside in the nucleus
15
Q
Weighted Average Equation
A
(% abundance x atomic mass) + add however many it asks
