PDF Unit 1 Lesson 5 Bill Nye Atoms and Molecules 7. Atoms are the basic BUILDING BLOCKS of all matter. 8. When atoms combine, they can make MOLECULES 9. All matter is made of ATOMS and MOLECULES 10. Water is TWO parts HYDROGEN and ONE part OXYGEN. We know this because water can be split apart by ELECTROLYSIS 11. To "see" the spaces in matter, add one cup of water and one cup of ALCOHOL.