atoms, elements and compounds

atoms, elements and compounds

1. atoms

   • the smallest part of an element
   • everything is made from atoms

2. elements

   • substance made of one atom only
   • atoms in a particular element are the same as each other

3. compounds

   • a substance that contains atoms of two or more
   • water= compound of hydrogen and oxygen

4. molecules

   • collection of two or more atoms held together by chemical bonds