Believed that all matter on Earth was comprised of varying proportions of earth, wind, fire, and water
Who is Aristotle?
100
Elements given this name because they don't "associate" with other elements
What are the Noble Gases?
100
The one constant when comparing ions or isotopes of an element
What is the atomic number?
100
Increases by one with each step from left to right across the periodic table
What is valence electrons?
200
Mass of 1 amu, charge of +1
What is a proton?
200
When J.J. Thompson discovered that atoms were not indivisible but contained both positive material and negative electrons, he proposed this model
What is the Plum Pudding Model?
200
The shortest period in the whole table
What is Period 1?
200
A change in this can leave an atom with a charge
What is electron number?
200
Occupying the bulk of the Periodic Table, these elements are found to the left of the zig zag line
What are metals?
300
Specific spaces around the nucleus in which electrons can be found according to their energy
What are energy levels (or shells)?
300
The experiment Rutherford did that gave evidence to support his Planetary Model of the atom
What is the Gold Foil Experiment?
300
Highly reactive metals, never found uncombined in nature
What is the Alkali Metal group?
300
This atomic mass for each element in the Periodic Table is found by calculating the weighted average of these
What are isotopes?
300
Because this increases, metals become more reactive as you move down a group in the Periodic Table
What is atomic radius? (or number of energy levels/shells)
400
The usual distribution of electrons before picking up energy and where they return when they lose that acquired energy
What is ground state?
400
Max Planck's work with the wave/particle duality of light inspired this scientist to quantize the atom creating energy levels in which electrons travel
Who is Neils Bohr?
400
A family of nonmetals characterized by being highly reactive because they have 7 valence electrons in their outer energy level
What is the Halogen group?
400
All 40 of them have a possible charge of +2 when forming ions
What are the Transition Metals?
400
Due to it's small radius and comparatively large nuclear charge, this nonmetal is the most reactive of all
What is fluorine?
500
In an unreacted atom, the number of these two particles is always the same
What are protons and electrons?
500
When this scientist proposed his model of an indivisible atom unique for each element, he had experimentally supported Democritus' beliefs
Who is John Dalton?
500
Their behavior depends upon what other elements they are hanging with
What are metalloids?
500
This common metal found in pop cans forms this ion when reacting
What is Al+3?
500
Two elements anyone could expect to act much like magnesium
What are (two of the following) calcium, barium, beryllium, strontium, and radium?