1. Atoms and Elements and Compounds: Are they Related? BGJHS Science 7 th Grade

2. ATOMS ALL MATTER IS MADE OF ALL MATTER IS MADE OF ATOMS Definition: ATOMS ARE THE Definition: ATOMS ARE THE SMALLEST PIECE OF MATTER and CANNOT BE BROKEN DOWN INTO A SIMPLER SUBSTANCE.

3. ATOMS HAVE ATOMS HAVE 3 BASIC PARTS (Subatomic Particles) PROTONS NEUTRONS ELECTRONS

4. – PROTONS (POSITIVE CHARGE) – ARE FOUND IN THE NUCLEUS AND MAKE UP MOST OF THE MASS OF THE ATOM. – VERY IMPORTANT!!! The number of protons an atom has tells you what kind of atom it is!!!!

5. The Atomic Number is the number of Protons Pg. 158

6. – NEUTRONS (NO CHARGE) ARE FOUND IN THE NUCLEUS MAKE UP PART OF THE MASS OF THE ATOM

7. Finding the Number of Neutrons for an Atom The protons and neutrons make up the mass of an atom. If you know the protons (atomic number) then you can find the number of neutrons by subtracting the atomic mass from the # of protons (atomic number). atomic mass - # of protons = # of neutrons

8. Isotopes Atoms of the same element that have a different number of neutrons. EX: Carbon Carbon-12Carbon-13Carbon-14

9. Isotopes & Radioactive Decay Atoms are most stable when they have the same number of Pro/Neu in the nucleus… So, having more neutrons causes atom to be unstable & “repulsion” builds up. Nucleus becomes more stable when the extra particles are released & energy is given off. RD is the release of extra nuclear particles & energy.

10. – ELECTRONS (NEGATIVE CHARGE - ) FOUND IN THE ELECTRON SHELL (cloud) ORBITING THE NUCLEUS. FOUND IN THE ELECTRON SHELL (cloud) ORBITING THE NUCLEUS. TAKES UP MOST OF THE SPACE IN AN ATOM. TAKES UP MOST OF THE SPACE IN AN ATOM. The # of electrons = the # of protons The # of electrons = the # of protons

11. Valence Electrons Outermost electron(s) in the cloud/shell 8 is the magic number!!!!!! (octet rule)

12. Ions Atom where the total number of electrons does not equal the total number of protons (atom will have a pos or neg charge) – Cation= pos (loss of e-) – Anion=neg (gain of e-) – EX: Fe 2+, Al 3+, O 2-

13. 9.17.00 1:37 PM13 3.3 Periodic Table Periodic Table: electron behavior The periodic table can be classified by the behavior of their electrons

14. Label the atom below on your packet! What type of atom is this? How do you know?

15. Atomic Size -A typical atom is about one ten-billionth of a meter in diameter. (THAT’S REALLY, REALLY SMALL AND WHY WE CAN’T SEE THEM WITH A REGULAR MICROSCOPE) -ATOMIC MASS = Protons + Neutrons. -Most of the atomic mass comes from the nucleus. -Electrons weigh very little. That is why they do not add to the mass of the atom. -They DO contribute to the SIZE.

16. Isotopes & Mass Number So if protons and neutrons contribute to mass, if we have a different number of neutrons, will the mass be affected? EX: since C-14 has 8 neutrons, the mass number is 14amu instead of 12amu (C-12).

17. Let’s Break for Questions??? How many protons should Hydrogen have? How about Oxygen? Which particles are located in the nucleus of an atom? Where are the electrons located?

18. Discovery of the Atom (pg. 80) By the early 1800’s, John Dalton proposed that all substances are made up of atoms. In 1898, J.J. Thomson, proposed that atoms are made up of smaller parts. In 1911, Ernest Rutherford, proposed that atoms have electrons and a positively charged nucleus.

19. 1)All matter is made of atoms. Atoms are indivisible and indestructible. 2) All atoms of a given element are identical in mass and properties 3) Compounds are formed by a combination of two or more different kinds of atoms. 4) A chemical reaction is a rearrangement of atoms. Dalton’s Atomic Theory

20. Niels Bohr’s model of the atom Electrons revolved around the nucleus in circular paths called orbits.

21. Current Atomic Theory: Electron Cloud Model Electrons travel in regions of various thicknesses called clouds (shells).

23. ELEMENTS ARE MADE OF ONLY 1 KIND OF ATOM. SOME COMMON ELEMENTS – HYDROGEN (H), HELIUM (He), OXYGEN (0), – Notice that the first letter is capital and the next letter is lower case.

24. ELEMENTS DEFINITION: PURE SUBSTANCES MADE OF ONLY 1 KIND OF ATOM. ARE THE BUILDING BLOCKS OF MATTER. CANNOT BE BROKEN DOWN INTO A SIMPLER SUBSTANCE. HAVE THEIR OWN UNIQUE SET OF PROPERTIES THAT NO OTHER ELEMENT HAS.

25. ELEMENTS There are 92 naturally occurring elements on the periodic table. This means they are in nature and not made in a laboratory by scientists. As of this year (2011) there are 118 confirmed elements. There are 4 more under investigation and scientific testing.

26. Elements Most Elements – react with water or oxygen – are rarely found alone in nature – easily undergo a chemical change

27. Let’s Stop for Questions What type of atoms make up the element Lithium? Carbon? Sodium?

28. Atoms and Elements Activity As a group, look at the food labels on the items at your table. Make a list of the items in the left hand side column and in the right hand side column make a list of any elements found in that substance. You may use your periodic table to help you identify the elements.

29. The food item would be: Cooked Ham What are the elements that are found on this food label?

30. QUESTIONS???? What are the most commonly occurring elements in the food labels? What items seemed to have the most amount of elements in them? Can you predict what that means about the food item? Why do you think the baby formula has such a variety of elements? Can you predict what the other items on the food label are if they are not elements?

31. Wrap Up Use your dry erase boards to write answers and hold them high!!! Protons have what charge? Electrons have what charge? Which parts of an atom make up the mass of the atom? Elements are made up of? The element lead is made up of what kind of atoms?

32. Periodic Table The periodic table is an organized table of each element. Each box gives information about each type of element found on Earth.

33. 9.17.00 1:37 PM33 3.3 Periodic Table Dmitri MendeleevDmitri Mendeleev (1869) Dmitri Mendeleev In 1869 Mendeleev and Lothar Meyer (Germany) published nearly identical classification schemes for elements known to date. The periodic table is base on the similarity of properties and reactivities exhibited by certain elements. Later, Henri Moseley ( England,1887-1915) established that each elements has a unique atomic number, which is how the current periodic table is organized. http://www.chem.msu.su/eng/misc/mendeleev/welcome.html

34. ELEMENTS ARE ORGANIZED IN THE PERIODIC TABLE ACCORDING TO ATOMIC NUMBER.

35. ELEMENTS ARE ORGANIZED IN THE PERIODIC TABLE OF ELEMENTS ACCORDING TO THEIR SIMILAR CHARACTERISTICS 3 major groups: metals, nonmetals and metalloids See pg. 57 in book

36. Elements & their symbols SOME COMMON ELEMENTS HYDROGEN (H), HELIUM (He), OXYGEN (0), Notice that the first letter is capital and the next letter is lower case. Gold- Au (Aurum) Iron- Fe (Ferrum) Lead- Pb (Plumbum)

37. Element Info in Each Box Atomic weight Atomic Number Symbol Name

38. Information from the periodic table Atomic Number- Number of Protons in an atom Silver = 47 protons

39. Arrangement of the Periodic table Periods – Rows are called periods. The elements in these rows change conductivity and number of electrons as you move across the table. Groups – Columns are called groups or families. These elements have the same properties because of the number of electrons.

40. How is the Periodic Table Organized? Even though they skip some squares in between, all of the rows go left to right. When you look at a periodic table, each of the rows is considered to be a different period Periods

41. 9.17.00 1:37 PM41 3.3 Periodic Table Across the Periodic Table Periods: Are arranged horizontally across the periodic table (rows 1-7) These elements have the same number of valence shells. 2nd Period 6th Period

42. Groups When a column goes from top to bottom, it's called a group or family. Groups are often called families because these elements seem to be related. **Elements in the same group show similarities in their chemical and physical properties.

43. 9.17.00 1:37 PM43 3.3 Periodic Table Down the Periodic Table Family: Are arranged vertically down the periodic table (columns or group, 1- 18 or 1-8 A,B) These elements have the same number electrons in the outer most shells, the valence shell. Alkali Family: 1 e- in the valence shell Alkali Family: 1 e- in the valence shell Halogen Family: 7 e- in the valence shell Halogen Family: 7 e- in the valence shell

44. 9.17.00 1:37 PM44 3.3 Periodic Table Reading the Periodic Table: Classification Nonmetals, Metals, Metalloids, Noble gases

45. 9.17.00 1:37 PM45 3.3 Periodic Table Periodic Table: Metallic arrangement Layout of the Periodic Table: Metals vs. nonmetals Metals Nonmetals

46. 9.17.00 1:37 PM46 3.3 Periodic Table Infamous Families of the Periodic Table Notable families of the Periodic Table and some important members: Alkali Alkaline (earth) Transition Metals Noble Gas HalogenChalcogens

47. 9.17.00 1:37 PM47 3.3 Periodic Table Alkali Group -Group #1 -1 valence electron in outer shell -very reactive with water & other elements -low densities & melting points

48. 9.17.00 1:37 PM48 3.3 Periodic Table Alkaline Earth Group -Group #2 -2 valence electrons in outer shell -very reactive but not as much as alkali -denser, harder & higher melting points

49. 9.17.00 1:37 PM49 3.3 Periodic Table Transition Metals -Groups 3-12 -Valence electrons vary -Usually found combined with other elements -higher melting points, good conductors

50. 9.17.00 1:37 PM50 3.3 Periodic Table Halogen Group -Group #17 -7 valence electrons in outer shell -most combined to make salts (salt formers) -most are non-metals

51. 9.17.00 1:37 PM51 3.3 Periodic Table Noble Gas Group -Group # 18 -8 valence electrons in outer shell (the happy gases! ) -NOT REACTIVE

52. 9.17.00 1:37 PM52 3.3 Periodic Table Periodic Table: Metallic arrangement Layout of the Periodic Table: Metals vs. nonmetals Metals Nonmetals

53. 9.17.00 1:37 PM53 3.3 Periodic Table Summary Periodic Table Periodic Table: Map of the Building block of matter Type Type: Metal, metalloid and Nonmetal Groupings: Representative or main, transition and Lanthanide/Actanides Family Family: Elements in the same column have similar chemical property because of similar valence electrons Alkali, Alkaline, halogens, noble gases Period: Period: Elements in the same row have valence electrons in the same shell.

54. The Periodic Table Of Elements Elements are classified: *Metals *Nonmetals *Metalloids Xenon Scandium

55. Properties of a metal * Good conductors – conducts heat or electricity *Malleable - flattened *Ductile – can be made into wires *Shiny- you can see you reflection Iron Gold Magnesium

56. Properties of a Nonmetal *Not malleable – cannot be flattened *Not shiny *Poor conductors Helium Chlorine Bromine

57. Properties of Metalloids Semiconductors – Average conductors Shiny but brittle Arsenic Silicon Boron

58. Periodic Table: Metallic arrangement Layout of the Periodic Table: Metals vs. nonmetals Metals Nonmetals

59. GOLD (AU) Sulfur Silver

60. ELEMENTS IN OUR BODIES IODINE

61. 1.Oxygen (65%) 2.Carbon (18%) 3.Hydrogen (10%) 4.Nitrogen (3%) 5.Calcium (1.5%) 6.Phosphorus (1.0%) 7.Potassium (0.35%) 8.Sulfur (0.25%) 9.Sodium (0.15%) 10.Magnesium (0.05%) 11.Copper, Zinc, Selenium, Molybdenum, Fluorine, Chlorine, Iodine, Manganese, Cobalt, Iron (0.70%) 12.Lithium, Strontium, Aluminum, Silicon, Lead, Vanadium, Arsenic, Bromine (trace amounts) 99% of the mass of the human body is made up of only six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Every organic molecule contains carbon. Since 65-90% of each body cell consists of water (by weight), it isn't surprising that oxygen and hydrogen are major components of the body

62. Elements in the body OxygenCarbonHydrogenNitrogen CalciumPhosphorusPotassiumSodium ChlorineMagnesiumSulfur

63. GASES FLUORINE KRYPTON NEON NITROGEN

64. Atoms to Elements to ???

65. ELEMENTS & COMPOUNDS ARE THE BASIC BUILDING BLOCKS OF MATTER EACH ELEMENT & COMPOUND HAS SPECIFIC PROPERTIES