1. Periodic Table Chapter 1

2. Big Bang Theory The idea that the universe was originally extremely hot and dense at some finite time in the past and has since cooled by expanding to the present state and continues to expand. Formation of protons and neutrons in the first few minutes Formation of hydrogen and helium Formation of stars (which then formed other elements by fusion)

4. Georges Lemaître (1894-1966) Belgian priest, physicist, and astronomer First person to propose idea of “primeval atom” to explain galaxies moving away from each other (1929) Later became Big Bang Theory

5. Evidence of Big Bang Red Shift: Shift of absorption bands toward red end of spectrum Edwin Hubble (1889-1953) 1927 – Showed evidence for galaxies moving apart (red shift)

6. Cosmic Background Radiation Left over energy from big bang Discovered in 1964

7. Particle accelerators Discovery of particles to show that energy can be converted into particles which combine to form protons

8. Elements and the Big Bang theory Hydrogen and Helium Created in the Big Bang Heavier elements (hydrogen to iron) Created in stars by fusion Even heavier elements (up to uranium) Created in supernova (death of star – explosion) Elements beyond uranium Manmade

9. Abundance of elements in the UNIVERSE Hydrogen 80% Helium 10% Oxygen 2% All other elments 8% Abundance of elements on the EARTH Oxygen 49% Silicon 25% Aluminum 7% All other elments 19%

10. How can scientists tell which elements are present in stars and other places in the universe? Spectral lines Light from stars Pattern of light given off by an elements electrons

11. History of the Atom

12. Democritus and Greek Philosophers Used reason and logic (not experimentation) Democritus - matter made of tiny, indivisible, solid objects called “atomos” Greek philosophers rejected this idea

13. Late 1700s – Study of reactions led to new ideas Law of conservation of mass: Mass can’t be created or destroyed by ordinary chemical or physical reactions

14. Late 1700s – Study of reactions led to new ideas Law of definite proportions: A compound contains the same proportions of mass regardless of sample size Ex. NaCl will always be 39.9% Na and 60.1% Cl

15. Late 1700s – Study of reactions led to new ideas Law of multiple proportions: If two or more compounds of the same two elements exist, then the ratio of the masses are ratios of whole numbers Ex. C and O can combine to form both CO and CO 2

16. John Dalton Billiard ball model (1803) John Dalton viewed the atom as a small solid sphere.

17. John Dalton’s Atomic Theory: (Early 1800s) 1. All matter is made of tiny particles called atoms 2. Atoms are indivisible (can’t be broken into smaller particles). During a chemical reaction, atoms are rearranged, but they do not break apart, nor are they created or destroyed. 3. All atoms of a given element are identical in mass and other properties. 4. Atoms of different elements are different in mass and other properties 5. Atoms of one element can combine with atoms of another element to form compounds – new, complex particles. In a given compound, however, the different types of atoms are always present in the same proportions.

18. Modern Atomic Theory (slight changes to Dalton’s theory) 2. Atoms CAN be divided – protons, neutrons, and electrons – nuclear reactions can split an atom 3. Atoms of the same element CAN be different - isotopes and ions

19. Models of the Atom Atom: The smallest particle of an element that still has the chemical properties of that element (reactivity, etc.)

20. Modern understanding of the atom – three subatomic particles: Protons Neutrons Electrons Nucleus

21. Discovery of the Electron

22. J. J. Thompson

23. J. J. Thomson Experiment: Cathode ray tube (1897) Discovered electron!!! Electron is negatively charged Measured charge-to-mass ratio of electron

24. Thomson’s Plum Pudding Model

26. Robert Millikan

27. Experiment: Oil drop experiment (1909) Measured charge of electron Both charge of electron and charge-to-mass ratio were used to determine the mass of an electron Mass of electron is 1/1837 mass of hydrogen atom

28. Discovery of the nucleus

29. Ernest Rutherford

30. Experiment: Gold foil experiment Discovered nucleus!!!! All mass of an atom is in the nucleus Nucleus is VERY massive

32. Rutherford’s model of the atom

34. Atomic Mass and the Mole

35. Relative Atomic Mass Units of grams are TOO LARGE for atoms! Relative atomic mass – compare to small particles – amu – “atomic mass units”

36. Average atomic mass Average atomic mass: weighted average mass of all isotopes of an element Weighted by % abundance of isotopes Example: 69.17% Copper-63 30.83% Copper-65 Find average atomic mass on the periodic table Molecular mass of individual compounds, or formula mass of individual formula units found by adding individual atomic masses. Average atomic mass = 63.55 amu (NOT 64 amu – because it’s weighted)

37. Units of amu are used for measuring single atoms, molecules, or formula units

38. The Mole 1 mole = 6.02 × 10 23 particles It is the number of atoms in exactly 12.0 g of carbon-12 Avogadro’s number

39. What is a mole? A counting number (like a dozen) – If you have a dozen cookies, how many do you have? – If you have a mole of cookies, how many do you have? – If you have 3.5 dozen cookies, how many do you have? – If you have 3.5 moles of cookies, how many do you have?

40. How big is a mole? It is HUGE. HUGE. HUGE. A mole of basketballs would fill four bags the size of the earth. If every person on earth counted out atoms during his or her entire life, counting an atom every second, it would take 3 million years to count out a mole of atoms.

41. Molar Mass Mass of one mole of a substance Units are g/mol Find molar mass on periodic table Molar mass of compounds found by adding individual molar masses

42. Units of g/mol (grams per mole) are used for measuring a mole of particles

43. Practice What is the molar mass of each of the following elements? – Sodium (Na) – Nickel (Ni) – Xenon (Xe)

44. Practice What is the molar mass of each of the following compounds? – H 2 O – NH 3 – C 2 H 6 O

45. REMEMBER: Atomic mass and molar mass are the same number, just different units.

47.  Dmitri Mendeleev (1869, Russian) › Organized by increasing atomic mass. › Grouped by properties › Some discrepancies.

48.  Dmitri Mendeleev (1869, Russian) › Predicted properties of undiscovered elements.

49.  Henry Moseley (1913, British) › Organized by increasing atomic number. › Fixed problems with Mendeleev’s arrangement.

51.  Metals  Nonmetals  Metalloids

52. ss pp dd ff Main group

53.  Families › Similar valence e - within a group result in similar chemical properties

54.  Alkali Metals  Alkaline Earth Metals  Transition metals  Inner transition metals  Halogens  Noble Gases

55. METALSMETALLOIDSNONMETALS Malleable/ductileLess malleable than metals, but not as brittle as nonmetals Brittle

56. METALSMETALLOIDSNONMETALS Malleable/ductileLess malleable than metals, but not as brittle as nonmetals Brittle Conduct electricitySemiconductorsDo not conduct electricity

57. METALSMETALLOIDSNONMETALS Malleable/ductileLess malleable than metals, but not as brittle as nonmetals Brittle Conduct electricitySemiconductorsDo not conduct electricity Shiny (lustrous)Dull

58. METALSMETALLOIDSNONMETALS Malleable/ductileLess malleable than metals, but not as brittle as nonmetals Brittle Conduct electricitySemiconductorsDo not conduct electricity ShinyDull Solid at room temperature (all except 1) Solid at room temperature Some solid, some gas at room temperature (1 liquid at room temp)

59. Choose from the following list of elements to answer the questions below: Gold (Au)Oxygen (O)Krypton (Kr)Silicon (Si) Magnesium (Mg)Iron (Fe)Boron (B)Sulfur (S) Which elements you would expect to be: Brittle: Sulfur, (Oxygen and Krypton would be if they were solid, but they’re both gases at room temperature) Malleable: Gold, Magnesium, Iron Conductive: Gold, Magnesium, Iron Somewhat brittle but somewhat malleable: Boron, Silicon Shiny: Gold, Magnesium, Iron Gold, Magnesium, Iron Poor conductors: Sulfur, Oxygen, Krypton

60. ALKALI METALS ALKALINE EARTH METALS HALOGENS NOBLE GASES TRANSITION METALS INNER TRANSITION METALS METALLOIDS METALS NONMETALS