Match the following terms with their definitions: words 1.pure substance 2.matter 3.atom 4.molecule 5.element defintitions 1. the fundamental building block of all substances and whose properties determine the properties of an element made of this particle 2. anything that occupies space and has mass 3. any compound resulting from sharing of electrons between two or more elements 4. a substance that has a fixed composition such as elements and compounds 5. a substance that contains only one kind of atom that cannot be broken down to simpler substances