Matter + phase changes

solids

matter that has a definite shape and a definite volume

liquids

matter that has a definite volume but takes the shape of its container

Gases

matter that takes the shape of its container and fills the available space

pure substance

has a uniform and unchanging composition

mixture

combination of 2 or more pure substances each one keeps its properties

element

pure substance made of one type of atom

compound

pure substance made of two or more atoms of different elements joined by chemical bonds 

heterogenous mixture

does not blend smoothly substances remain distinct

homogenous mixture

constant composition throughout the mixture

physical properties of matter

a characteristic that can be observed or measured without changing what the substance is 

extensive properties

depend on how much stuff there is

intensive properties

the same regardless of how much you have. Inherent to the substance

chemical properties of matter

ability of a substance to combine with or change into another substance

physical changes

alters a substane without changing its chemical composition

chemical changes

substances changing into new substances making or breaking chemical bonds

phase changes

changing the state of matter

triple point

temperature and pressure conditions where all three phases coexist

critical point

shows the point where substances can no longer exist as a liquid (it is then a fluid)

gas to solid 

deposition

solid to gas

sublimation

evaporation

heat adds energy to the molecules at the top of water making them become a gas

boiling

heat is added directly, gas forms in the liquid then escapes