Atomic Theorists

1. Atomic Theorists How We Got To Where We Are Now!!

2. Atomic TheoristsAt the conclusion of our time together, you should be able to: List 5 major atomic theorists If possible, give a piece of equipment or experiment for which they are noted Draw their model of the atom List 3 basic laws of chemistry that were used to help develop the atomic theory

3. 15 Helpful Hints On The Lab Report from Mr. T’s Vast Lab Experience!!! Hint #1. When you don't know what you are doing, do it neatly. 

4. Who: Democritus • When: 400 B.C. • Where: Greece • What: Matter was made of indivisible substances he called atomos (1st talk of the atom)

5. Who: Aristotle What: All matter is a combination of fire, air, earth or water When: 350 B.C. Where: Greece

6. Law of Conservation of Mass • Who: Antoine Lavoisier • Matter can't be created or destroyed • When: 1785 • Where: France

7. Law of Definite Proportions • Who: Joseph Proust • What: Elements – Compounds put together in fixed ratios of small whole numbers ex. C + O2 CO2 • When: 1797 • Where: France

8. Happy Birthday Dirge • Happy Birthday, Happy Birthday, • So you’ve aged another year. • Now you know that Death is near. • Happy Birthday, Happy Birthday!

9. Law of Multiple Proportions • Who: John Dalton • What: Two elements can form more than one compound The subscripts of the elements in the compounds will be small whole numbers. • C + O2 CO2 • C + O2 CO • Where: England • When: 1803

10. 2 Law of Multiple Proportions 2.1

11. Who: John Dalton • What: Solid Sphere Model (1st atomic theory) • 1. Matter is composed of indivisible particles • 2. All atoms of a particular element are identical • 3. Different elements have different atoms • 4. Atoms combine in certain whole-number ratios • 5. In a chemical reaction, atoms are merely rearranged to form new compounds; they are not created, destroyed, or changed into atoms of any other elements.

12. + 16 X 8 Y 8 X2Y Law of Conservation of Mass 2.1

13. Problems with Dalton’s Theory

14. Problems with Dalton’s Atomic Theory? 1. Matter is composed of indivisible particles Atoms can be divided, but only in a nuclear reaction 2. All atoms of a particular element are identical Does not account for isotopes (atoms of the same element but a different mass due to a different number of neutrons)! 3. Different elements have different atoms Yes! 4. Atoms combine in certain whole-number ratios Yes! Called the Law of Definite Proportions 5. In a chemical reaction, atoms are merely rearranged to form new compounds; they are not created, destroyed, or changed into atoms of any other elements. Yes, except for nuclear reactions

15. Remember to make clear and concise statements with your observations!!!

16. Who: J.J. Thomson • What: Atoms are not the smallest particle • Conducted experiment with a Cathode • Ray Tube • Particles had a negative charge (discovered electrons) • Model = plum pudding • jello fruit salad When: 1897 Where: England

17. Cathode Ray Tube

18. J.J. Thomson, measured mass/charge of e- (1906 Nobel Prize in Physics)

19. 2.2

20. Questions about teenage men answered by teenage women!!! Q: Why do little boys whine? A: They are practicing to be young men.

21. Who: Robert Millikan • What: • Experiments to determine mass of electron • Conducted the oil drop experiment • Verified that electron is negatively charged; • 1.6 x 10 -19 coulombs • No new model • Where: America • When: 1910

22. Millikan’s Oil Drop Experiment

23. Measured mass of e- (1923 Nobel Prize in Physics) e-charge = -1.60 x 10-19C Thomson’s charge/mass of e- = -1.76 x 108 C/g e- mass = 9.10 x 10-28 g 2.2

24. A prayer for her teenage boyfriend by a teenage young woman!!! Dear Lord, I pray for Wisdom to understand my guy;  Love to forgive him; and Patience for his moods. Because, Lord, if I pray for Strength,  I'll beat him to death!!!!

25. Who: Ernest Rutherford • What: • Conducted Gold Foil experiment • Proved nucleus is dense, positively charged core of atom • When: 1911 • Where: America • Model = Stationary Planetary

26. Rutherford’s Experiment Gold Foil Experiment

27. (1908 Nobel Prize in Chemistry) • particle velocity ~ 1.4 x 107 m/s (~5% speed of light) atoms positive charge is concentrated in the nucleus proton (p) has opposite (+) charge of electron mass of p is 1840 x mass of e- (1.67 x 10-24 g) 2.2

29. Results of foil experiment if Plum Pudding model had been correct.

30. What Actually Happened

31. Rutherford’s Model of the Atom atomic radius ~ 100 pm = 1 x 10-10 m nuclear radius ~ 5 x 10-3 pm = 5 x 10-15 m If the atom is Cleveland Stadium Then the nucleus is a marble on the 50 yard line 2.2

32. A little known fact concerning teenage boyfriends!!! While creating man, God promised women that good and ideal boyfriends would be found in all corners of the world......... ......then He made the earth round.

33. Who: Niels Bohr • What: Pulsating Planetary Model • Electrons can move between energy levels • When: 1913 • Where: Denmark

34. Who: James Chadwick What: • Confirmed existence of neutron • No new atomic model • When: 1932 • Where: England

35. a+ 9Be 1n + 12C + energy Chadwick’s Experiment (1932) H atoms - 1 p; He atoms - 2 p mass He/mass H should = 2 measured mass He/mass H = 4 neutron (n) is neutral (charge = 0) n mass ~ p mass = 1.67 x 10-24 g 2.2

36. Interesting Name for a Boat!!

37. Atomic TheoristsLet’s see if you can: List 5 major atomic theorists If possible, give a piece of equipment or experiment for which they are noted Draw their model of the atom List 3 basic laws of chemistry that were used to help develop the atomic theory

38. Get Your Clicker!!!

39. The following diagram describes best the ideas of whom? Aristotle John Dalton J J Thomson Ernest Rutherford Democritus

40. What idea does the following diagram describe? • Solid Sphere Model • Stationary planetary model • Plum pudding model • Pulsating orbital model

41. Which law defines the following? H2 + O2  H2O2 H2 + O2  H2O • Law of conservation of mass • Law of definite proportions • Law of multiple proportions

42. Who is responsible for the following diagram? • Neils Bohr • John Dalton • J J Thomson • Ernest Rutherford • Millikan

43. Who of the following contributors to the Atomic Theory would come 4th on a time line? • Aristotle • John Dalton • J J Thomson • Ernest Rutherford 5. Democritus

44. Who used this piece of equipment to contribute to the Atomic Theory? • Neils Bohr • John Dalton • J J Thomson • Ernest Rutherford 5. Millikan

45. What does the following diagram describe? • Solid Sphere Model • Stationary planetary model • Plum pudding model • Pulsating orbital model

46. WHY GOD MADE MOMSAnswers given by 2nd grade school children to the following  questions:Why did God make mothers? 1.  She's the only one who knows where the scotch tape is. 2.  Mostly to clean the house. 3. To help us out of there when we were getting born.

47. The Atom Historical Models Family Feud Draw 4 historical models of atoms on a time-line. The correct model is one point, the correct name or person of the model is one point and the correct approximate time on the line is one point.

48. The Modern Atom Family Feud