| A | B |
|---|
| element | a natural or artificial substance that cannot be broken down into simpler substances by any means |
| proton | sub-atomic particle that has a positive charge and the same mass as a neutron |
| neutron | sub-atomic particle that has no charge (neutral) and has the same mass as a proton |
| electron | sub-atomic particle that has mass and a negative electrical charge |
| octet rule | atoms are most stable when they have 8 valence electrons in their outer shell |
| ionic bond | an attractive force between two ions with opposite charges |
| covalent bond | an attraction of two atoms for a shared pair of electrons that holds the atoms together |
| solid | matter that has a fixed volume and shape |
| liquid | matter that has a fixed volume but no fixed shape |
| gas | matter with no fixed volume or shape |
| mineral | naturally occurring, inorganic solid with a specific chemical composition and definite crystalline structure that forms from magma or supersaturated solutions |
| ore | a mineral that is mined for profit |
| igneous rock | magma that turns to solid |
| sedimentary rock | sediments pressed together |
| metamorphic rock | rocks that form from extreme heat and pressure |
| rock cycle | rocks transform into other types of rocks |
| atom | smallest particle of an element |
| nucleus | center of an atom, made of up neutrons and protons |
| chemical bond | forces that holds the atoms of elements together in a compound |
| hardness | measure of how easily a mineral can be scratched |
| luster | describes the metallic or nonmetallic way that a mineral reflects light |
| streak | color a mineral leaves when it is rubbed across an unglazed porcelain plate |
| cleavage | ability of a mineral to break easily and evenly along one or more flat planes |
| gem | rare, precious, highly prized mineral that can be cut, polish, used for jewelry |
| crystal | solid in which atoms are arranged in repeated patterns |
| magma | molten material found beneath Earth's crust |
| silicate | mineral that contains silicon and oxygen and usually one or more other elements |
