Science Ch 3 Elements and the Periodic table

1. Science Ch 3 Elements and the Periodic table 3.1

2. Starting Activity • Imagine you have a 5 drawer cabinet • You need to organize all the stuff in the pink bin(provided by teacher) into 5 categories(drawers) • Ex: Size, color, shape, use

3. Scientist also have to organize.... • BUT…. • Before we get to that we need to start back at the beginning with…..ATOMS!!!

4. How did the Atomic Theory Develop? • It’s hard to study atoms because they are so SMALL • Over the years, scientistshave made models to help us study the smallest particle

5. Dalton’s Atomic Theory • John Dalton thought that atoms were like smooth, hard balls that couldn’t be broken into smaller pieces

6. Dalton’s Atomic Theory cnt. • 1. Atoms can’t be divided • 2. All atoms are the same • 3. You can’t change atoms into another substance

7. Thomson’s Model • In 1897 Thomson discovered that atoms have negatively charged particles called electrons floating in a positive charge

8. Rutherford’s Model • In 1911 (Thomson’s student) Rutherford did a GOLD foil experiments on the atom • https://www.youtube.com/v/5pZj0u_XMbc • https://www.youtube.com/v/ecsgC1wSp5I

9. Shot light towards a gold foil • Some particles went straight through and others bounced back at large angles • This showed that there must have been something in the atoms of the gold foil big enough to bounce back a particle

10. Rutherford inferred (guessed) that all the positive charge must have been packed together • Nucleus – the positive center(protons) of an atom

11. Rutherford’s hypothesis was WRONG

12. Bohr’s Model • In 1913, Bohr suggested that the electrons have a specific orbit around the nucleus

13. Cloud Model • In 1920’s, scientists said electrons move freely in a cloudlike region • The electron’s movement is based on the amount of energy it has

14. Modern Model • In 1932, James Chadwick discovered the neutron (neutral particle with no charge) • The center of an atom is the nucleus with protons and neutrons. Electrons move around a cloudlike region.

15. Science Learning the Structure of Matter (3.1 cnt.)

16. Comparing Particle Masses • What are the 3 particles • 1. Electron • 2. Proton • 3. Neutron

17. Atoms are too small to use grams or kg to describe their mass, so we use AMU (atomic mass units)

18. Atomic Number • Every atom of an element has the same number of protons • The Atomic Number tells you how many protons are in that atom

19. Game: How many Protons are in .... • Potassium • Iron • Aluminum • Lithium

20. What is the mass of… • Titanium? • Flourine? • An element with 16 protons and 17 NEUTRONS? • 17 protons and 18 NEURONS? • WHAT DO YOU ADD TOGETHER to get the MASS?

21. Isotopes • All atoms of an element have the same number of ____________ • BUT, the number of neutrons can change--- that gives us an isotope

22. Get familiar with the element • http://www.sheppardsoftware.com/Elementsgames.htm

23. Organizing the Periodic Table 3.2

24. Mendeleev created the first periodic table • A Russian scientists who arranged the elements by their atomic mass • The atomic mass of an element is the average mass off all the isotopes

25. Mendeleev noticed a pattern of properties in the elements • What happened when each element was put in water?

26. The first periodic table in 1869 • It is arranged to show a pattern with their properties • The first one has many missing/blank spots

27. Information on the Periodic Table

28. How is the Periodic Table Useful? 3.2 cnt.

29. An element’s properties can predict where it will go on the periodic table • **Rows are called periods

30. From Left  Right • Metals  Metalloids  Nonmetals

31. Columns are called groups • Numbered 1  18 • Elements in each Group have similar Properties Ex: Group 17 is very reactive, but 18 is nonreactive

32. Ex: Group 10 Since elements in the same groups have similar properties what properties do you think Darmstadtium? ??

33. RULES for ENERGY LEVELS • BOHR Models • 1. LEVEL 1 is closest to the nucleus. Can hold a MAXIMUM of 2e. • 2. Level 2 can hold a maximum of 8e. • 3. Level 3 can hold a maximum of 18e. • 4. Level 4 can hold a maximum of 32e.

34. Research Time!!! • Pick 2 of the groups from the periodic table (#1-18) and make a list of properties that they all have in common

35. Science Stations Expectations: • Today you will be moving to 5 different stations to help you practice all the information that we have learned so far in this chapter Voice Level: 2 Participation: Work together with your partners Work: Complete all the work at each station (Don’t waster your time) Leave the station like you found it (neat and organized and NO writing on the cards/direction sheet) Movement: Move quietly when the timer rings

36. Station #1 : • Station #2: • Station #3: • Station #4: • Station #5:

37. Science Quiz Tomorrow Ch 3.1-3.2

38. 1. What is the basic building block of matter? • Atoms

39. 2. _________ model of the atom was like a chocolate chip cookie • Thomson’s

40. 3. What are negatively charged particles? • Electrons

41. 4. Who’s model of the atom was just a circle? • Dalton

42. 5. What particle has no charge? • Neutron

43. 6. What 2 particles are in the nucleus? • Protons and Neutrons

44. 7. Who did a gold foil experiment? • Rutherford

45. 8. Who’s model has rings like a tree to represent energy levels ? • Bohr’s

46. 9. Label this diagram

47. 10. How do I know how many protons are in an element? • Look at the atomic number

48. 11. Who was the first one to organize the periodic table? • Mendeleev

49. 12. What was wrong with the first periodic table? • It wasn’t complete • Missing elements

50. 13. Label this diagram