________ are unique to each element, and could be used to identify elements.
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Neutrons
________ are also located in the nucleus.
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Octet Rule
________: States that the atoms would tend to lose /gain /share electrons in order to acquire a full set of valence electrons, which is 8 electrons.
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Ernest Rutherford
________: Gold foil experiment involved during the firing of radioactive particles through thin gold foils and observed them.
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Billiard Ball Model
________: John Dalton viewed the atom as a small solid sphere.
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Composition
________ is in a fixed ratio: meaning the ratio cant be varied and the compound still being the same thing.
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Electrons
________ have negative charge.
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electron
When the ________ falls back down to the ground, it releases energy and gives off light energy or a spectrum.
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Greek philosopher
________ proposed that all matter was composed of tiny, indestructible particles called atoms (which is Greek for uncuttable)
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Plumb Pudding Model
________: J.J. Thompson proposed that the atom was a sphere of positive electricity with negative particles imbedded throughout after discovering the electron (1897)
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materials properties
Any of a(n) ________ that becomes evident during a chemical reaction.
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Examples
Any element on the periodic table
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A substance that are made up of 2+ different elements, and can be decomposed by chemical means into simpler substances
always in the same ratio by mass
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Example
Water (H2O) is always 2 hydrogen molecules and 1 oxygen molecule
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Example
Air
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Example
Chocolate Chip Cookies
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[EXTRA note
Allotropes are different structural modifications of an element… meaning theyll have different chemical and physical properties]
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Example
water and sand (filtering)
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composition is in a fixed ratio
meaning the ratio cant be varied and the compound still being the same thing
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Example
water and sand
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Example
water and alcohol
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Example
separation of plant pigments
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Examples
Boiling point, Taste, Odor, Dissolves in water, Luster, Density, Hardness, etc
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Examples
Flammability, Ability to Rust
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Democritus
a fifth century B.C
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Billiard Ball Model
John Dalton viewed the atom as a small solid sphere
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Plumb Pudding Model
J.J. Thompson proposed that the atom was a sphere of positive electricity with negative particles imbedded throughout after discovering the electron (1897)
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It looks like a plum pudding
)
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Electron Cloud Model
An atom consists of a dense nucleus composed of protons and neutrons surrounded by electrons that exist in different clouds at the various energy levels
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Ernest Rutherford
Gold foil experiment involved during the firing of radioactive particles through thin gold foils and observed them
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They determine the identity of each element
Also represents the atomic number
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Atomic Number
Numbers of Protons
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Atomic Mass
Numbers of Protons + Neutrons
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Valence Electrons
The amount of electrons an element has on their most outermost shell
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Octet Rule
States that the atoms would tend to lose/gain/share electrons in order to acquire a full set of valence electrons, which is 8 electrons
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Ground State
Electrons are in their lowest energy levels, or their normal energy levels
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Excited State
When heat, electricity, or light would move the electron up to different energy levels