1. Introduction to ATOMS

7. Electrons are always on the move.

8. Neutrons and protons are held together in the nucleus by the “strong” force, which has to overcome the electrical repulsion of the positively charged protons.

9. Electrons are held around the atom by the electrical attraction between their negative charge and the positive charge of the protons in the nucleus.

10. Protons = positive charge + Neutrons = neutral charge = no charge Electrons = negative charge - + -

12. The Periodic Table shows the Symbol, ATOMIC number, ATOMIC weight, and the name of each ELEMENT. SYMBOL ATOMIC NUMBER ATOMIC WEIGHT NAME H 1 1.008 Hydrogen

13. HYDROGEN Hydrogen has an Atomic number of 1. Hydrogen has an Atomic weight of 1.008 The symbol for hydrogen is H. H 1 1.008 HYDROGEN

14. HELIUM Helium has an Atomic number of 2. Helium has an Atomic weight of 4.00 The symbol for Helium is He. He 2 4.00 HELIUM

15. LITHIUM Lithium has an Atomic number of 3. Lithium has an Atomic weight of 6.94 The symbol for Lithium is Li. Li 3 6.94 LITHIUM

16. BERYLLIUM Beryllium has an Atomic number of 4. Beryllium has an Atomic weight of 9.01 The symbol for Beryllium is Be. Be 4 9.01 BERYLLIUM

17. BORON Boron has an Atomic number of 5. Boron has an Atomic weight of 10.81 The symbol for Boron is B. B 5 10.81 BORON

18. CARBON Carbon has an Atomic number of 6. Carbon has an Atomic weight of 12.01 The symbol for Carbon is C. C 6 12.01 CARBON

19. NITROGEN Nitrogen has an Atomic number of 7. Nitrogen has an Atomic weight of 14.01 The symbol for Nitrogen is N. N 7 14.01 NITROGEN

20. OXYGEN Oxygen has an Atomic number of 8. Oxygen has an Atomic weight of 16.00 The symbol for Oxygen is O. O 8 16.00 OXYGEN

21. FLUORINE Fluorine has an Atomic number of 9. Fluorine has an Atomic weight of 19.00 The symbol for Fluorine is F. F 9 19.00 FLUORINE

22. NEON Neon has an Atomic number of 10. Neon has an Atomic weight of 20.18 The symbol for Neon is Ne. Ne 10 20.18 NEON NUCLEUS