Definition: a pure substance

            is a subtance that is chemically formed and has chemical properties such as a melting and boiling point.

All elements are pure substances. And all compounds are pure substances like salt and water. They atrecpure substances because all of there atoms are the same like in neon no matter how small the sample is its still neon. All elements have certain chemical properties such as melting point and a boiling point. A pure substance such as salt has a certain chimical properties also. a none pure substance such as a pizza isnt the same throughout you could a piece of bacon in one bite or cheese in the other. pizza alsom doesnt have a certian melting and boiling point such as salt or neon pizza is made of several substances that are not chemicly bonded.                                    

 this is a pizza non pure substance.                   these enlarged salt crystals are pure                                                                              substances                                                   

SO WHAT??? SECTION: this term is helpful because it defines abunch of elements and compounds with certain defined chemical properties. 

www.littlecaesars.com/pizza/hot-n-ready_pizza.asp is were the pizza is located

elementary.vernier.com/products/proscope.html is were the salt crystals were located

ST3PH3N Q  .$+3P#3N.(stephen)