Atom
The smallest particle of an element that retains the composition of that element
Element
A substance that can not be Brocken down into simpler substances by ordinary chemical means
Compound
A substance that is formed when two or more different elements chemically combine in a fixed ratio
Mixture
A physical combination of different substances
Element molecule
A substance consisting of only one type of element chemically joined together
Chemical change
Is a change in the composition of reacting substances resulting in a new product being formed
Physical change
Is a type of change in which the form of matter is altered but one substance is not transformed into another
Valency
The amount of electrons lost gained or shared to complete the outermost energy level
