1. Atomic Structure Chapter 4

2. The Atom  The smallest particle of an element that retains its identity in a chemical reaction  A penny is about 200,000,000 copper atoms across

3. Just How Small Is an Atom?  Remember looking at these last year?  You would have to magnify them a billion times more to see the atoms they are made of.(1,000,000,000x)

4. The Atom  There are three kinds of particles that make up atoms.  These are called subatomic particles.

5. Protons & Neutrons  Proton (p + ) is positively charged  Neutron (n 0 ) has no charge  Both have the same mass (1.67 x 10 -24 g or 1 amu)

6. Electrons  Electron (e - ) is negatively charged  Much less mass than protons or neutrons (about 2000x less or 0 amu)  Are the cause for all of an element’s or compound’s behavior

7. Arrangement  At the center of an atom is the nucleus. Here are the atom’s protons and neutrons. Almost all of the atom’s mass.  Electrons are spread outside of and around the nucleus. They produce almost all of an atom’s volume (size)

8. How Do You Tell Them Apart?  Elements are different because they have different #’s of protons.  The # of protons is also an element’s Atomic Number.

9. Mass Number  The sum of the protons and the neutrons in an atom.  Can be used to find the number of neutrons an atom has. (Mass #) = (# of neutrons) + (Atomic #)

10. Isotopes  Atoms that have the same number of protons (they have to) and electrons, but different numbers of neutrons.  When atoms begin to have more than enough neutrons, they become unstable. This is radioactivity.

11. Starting on p. 91-102  What year or time period…  What country the person was from or where they did their work….  What their contribution or discovery was….  Why it’s significant……

12. Democritus

13. John Dalton

14. Michael Faraday

15. Benjamin Franklin

16. J.J. Thomson

17. Robert Millikan

18. Henri Becquerel

19. Pierre and Marie Curie

20. Ernest Rutherford

21. Are These the Only People? NO !!!  James Chadwick-discovers the neutron in 1932  Neils Bohr-a GIANT in the field of science  Albert Einstein-perhaps you’ve heard of him  Werner Heisenberg-quantum theory  Joseph Priestley  …and many more

22. 1 2 34 5678

23. Ions (charged particles)  Monatomic (1 atom) ions have different numbers of protons and electrons.  An atom has no charge because (# of p + ) = (# of e - )  An ion has a charge because there is a charge imbalance (# of p + ) ≠ (# of e - )  Charge = (# of p + ) – (# of e - )

24. Ions (charged particles)  Monatomic (1 atom) ions have different numbers of protons and electrons. For example: H +, Cl -, Na +, O 2-.  Polyatomic ions (more than 1 atom) are small molecules that possess an excess of electrons, so they have a charge. For example: NH 4 +, PO 4 3-, SO 4 2-, OH -.

25. Ionic Compounds  Formed from the combining of ions.  ALWAYS a metal bonded to a non- metal.  Positive ion is a cation.  Negative ion is an anion.  We will be working with BINARY compounds (two parts).

26. Naming Ionic Compounds  Cation is always written first.  Identify the cation and name it.  Identify the anion and name it.

27. Formulas of Ionic Compounds  Identify the cation and the anion.  Balance the charges. You need equal amounts of + and – charge. (Criss-cross)  Write the formula, with a subscript for any ion that there is 2 or more of.  If you use 2 or more of a polyatomic ion, it needs parentheses.

28. Matter Pure Substances Elements Metals Non-Metals Compounds Ionic Compounds Mixtures Homogeneous Mixtures Heterogeneous Mixtures

29. Matter Pure Substances Elements Metals Non-Metals Compounds Ionic Compounds Hydrates Mixtures Homogeneous Mixtures Heterogeneous Mixtures

30. Hydrates  Ionic compounds with water trapped in the crystal structure.

31. Naming Hydrates  Name the ionic part of the compound first.  Then name the hydrate part with a prefix and the word “hydrate”.  What are the prefixes????

32. Prefixes  1------mono  2------di  3------tri  4------tetra  5------penta  6------hexa  7------hepta  8------octa  9------nona  10----deca

33. Matter Pure Substances Elements Metals Non-Metals Compounds Ionic Compounds Hydrates Mixtures Homogeneous Mixtures Heterogeneous Mixtures

34. Matter Pure Substances Elements Metals Non-Metals Compounds Ionic Compounds Hydrates Covalent Compounds Mixtures Homogeneous Mixtures Heterogeneous Mixtures

35. Covalent Compounds  ALWAYS a nonmetal bonded to a nonmetal  Not bonded due to opposite electrical charges (like ionic compounds are)

36. Naming Covalent Compounds  Name the cation as an element.  Add a prefix to the cation if there are two or more.  Name anion as an ion  Add a prefix to the anion no matter how many there are.

37. Formulas for Molecules  The prefix in each part of the name tells you how many of component there are/is.

38. Matter Pure Substances Elements Metals Non-Metals Compounds Ionic Compounds Hydrates Covalent Compounds Acids Mixtures Homogeneous Mixtures Heterogeneous Mixtures

39. Acids  The cation for an acid is ALWAYS hydrogen.  The names for acids come from the anion in the acid.  The names for acids are as shown:  HCl-Hydrochloric Acid  HNO 3 -Nitric Acid  H 2 SO 4 -Sulfuric Acid  H 3 PO 4 -Phosphoric Acid  HCH 3 COO-Acetic Acid

40. 1 st Element Listed Metal Ionic-no prefixes Hydrogen Acid- memorized Nonmetal Molecular- prefixes