Atoms and Atomic Theory

1. Atoms and Atomic Theory Essential Questions: How and why has the Atomic Theory changed over time? How can we describe the molecular motion of the states of matter?

2. What is an Atom? • Atom: the smallest unit of matter that retains the identity of the substance https://www.youtube.com/watch?v=_lNF3_30lUE

3. Atoms • Matter is anything that takes up space and has mass. All matter is made of atoms. • Atoms are the basic building blocks of matter. They make up everything around us; Your desk, the board, your body, everything is made of atoms! • Atoms are too small to see without powerful microscopes. Scanning Tunneling Microscope 

4. What is Matter? • Anything that has mass and takes up space (volume) • Examples: • A brick has mass and takes up space • A desk has mass and takes up space • A pencil has mass and takes up space • Air has mass and takes up space These examples are considered matter because they have mass and take up space. Can you think of anything that would not be considered matter?

5. Atoms • Made up of: • protons • neutrons • electrons - + + + + - + - -

6. Subatomic Particles Three subatomic particles make up every atom:

7. Subatomic Particles

8. Protons ( p+ ) • Part of the nucleus • Have positive (+) charge

9. Neutron ( 0 ) • Part of the nucleus • Have neutral charge

10. Electrons ( e- ) • Orbit around the nucleus • Have negative (-) charge

11. Atomic Structure • Atoms have 2 regions 1) Nucleus: the center of the atom that contains mostof the mass of the atom. 2) Electron cloud: surrounds the nucleus & takes up most of the space of the atom. Electron Cloud: (Surrounds nucleus) Nucleus

12. Atomic Structure There are two basic components in every atom: Electron Cloud Nucleus

13. Subatomic Particles • Electron Cloud: • Electrons orbit the nucleus. • Nucleus or “Core”: • Protons and Neutrons are found in the nucleus. https://www.youtube.com/watch?v=GLp9ihOYjjM

14. Atomic Theory Changes over time…

15. Atomic Theory • Because we can not see atoms, we use models to teach and learn about atoms. • The atomic theory has changed over time as new technologies have become available. • Remember: Scientific knowledge builds on past research and experimentation. https://www.youtube.com/watch?v=LhveTGblGHY

16. Atomic Theory Timeline

17. Atomic Theory Timeline

18. Atomic Theory Timeline

19. Atomic Theory Timeline Neutrons

20. Atomic Theory Timeline

22. Elements and the Periodic Table Essential Questions:How are elements organized in the periodic table?

23. Atoms and Elements There are billions of materials in our universe. Those materials are made up from about 100 elements only. https://www.youtube.com/watch?v=d0zION8xjbM

24. What is an Element? An element is a substance that is made from one kind of atom only. It cannot be broken down into simpler substances. atom An element An element

25. What is a compound? A compound is a substance that is made from more than one element. Atom 5 Atom 1 Atom 6 Atom 1 Atom 2 Atom 2 Atom 7 Atom 3 Atom 4 Atom 8 This compound made up of 2 different elements This compound made up of 8 different elements

26. A compound can be broken down into elements An element An element Thiscompound is made up of 3 different elements An element

29. The Periodic Table is a useful way to arrange elements. • The vertical columns (↕) are called groups. • The horizontal rows (↔) are called periods. • Elements in the same group have similar properties. • Three quarters of the elements are metals. • One quarter of the elements are non-metals. https://www.youtube.com/watch?v=xQu2eSeM66o

30. Organization of the Periodic Table • There are 18 Groups/ Columns (Up - Down) • There are 7 Periods (Left - Right) • 3 types of characteristics are arranged: • Metals – Left side, except Hydrogen (H) • Non Metals – Right side • Metalloids – In-between metals and nonmetals

31. Organization of The Periodic Table Period (Left-Right) Group/Family (Up and Down)

32. The Periodic Table https://www.youtube.com/watch?v=zGM-wSKFBpo

33. https://www.youtube.com/watch?v=rz4Dd1I_fX0

34. Reading the Elemental Box Essential Questions: Describe the location of the atomic number, symbol, and mass of an element by reading the Elemental Box. https://www.youtube.com/watch?v=t-Z5PlP6AL0

35. Reading the Elemental Box

36. Now look in your periodic table and find the symbols of the following elements as a class (Tell me the Atomic Number also) Copper …….. Iron ……….. Magnesium ……….. Chlorine ……….. Carbon ………… Sodium ……. Lead ………. Gold ……… Calcium …….. Fluorine ……….

37. Now look in your periodic table and find name that corresponds to the following symbol as a class

38. Iron Fe

39. Copper Cu

40. Nickel N

41. Fluorine F

42. Potassium K

43. Zinc Zn

44. Lithium Li

45. Aluminum Al

46. Oxygen O

47. Solving the atomic mass Essential Questions: How can we solve the number of protons, neutrons, and electrons an element contains? https://www.youtube.com/watch?v=tc9tEUqUmKw

48. Remember the Subatomic Particles Three subatomic particles make up every atom:

49. How do we find the number of Protons (P+) in an atom? • Atomic number (#)= # of protons in an atom • Ex: Hydrogen’s atomic # is 1 • hydrogen has 1 proton • Ex: Carbon’s atomic # is 6 • Carbon has 6 protons **The number of protons identifies the atom-it’s an atom’s fingerprint.

50. How do we find the number of Neutrons (n) in an atom? • Mass # = the # of protons + neutrons in the nucleus • Mass # - Atomic # = # of Neutrons Example (M.A.N.) Example: Lithium has an atomic # 3 of and a mass # of 7 • Protons = (same as atomic #)= 3 • Neutrons = (mass # - atomic #)= (7-3) = 4