Introduction to the Periodic Table

Transcription

1 Introduction to the Periodic Table Atomic Number Symbol Atomic Weight Element Compound Mixture

2 I am Dmitri Mendeleev! I made the PERIODIC TABLE!

3 What is the PERIODIC TABLE? oshows all known elements in the universe. oorganizes the elements by chemical properties.

4 How do you read the PERIODIC TABLE?

5 What is the ATOMIC NUMBER? othe number of protons found in the nucleus of an atom Or othe number of electrons surrounding the nucleus of an atom.

6 What is the SYMBOL? oan abbreviation of the element name.

7 What is the ATOMIC WEIGHT? othe number of protons and neutrons in the nucleus of an atom.

8 How do I find the number of protons, electrons, and neutrons in an element using the periodic table? o# of PROTONS = ATOMIC NUMBER o# of ELECTRONS = ATOMIC NUMBER o# of NEUTRONS = ATOMIC _ ATOMIC WEIGHT NUMBER

9 You've got Your Periods... 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 (Get it? Like PERIODic table.) quoted from

10 Periods = Rows In the periodic table, elements have something in common if they are in the same row. All of the elements in a period have the same number of energy levels. Every element in the top row (the first period) has one orbital for its electrons. All of the elements in the second row (the second period) have two orbitals for their electrons. It goes down the periodic table like that. quoted from

11 And you got your groups The periodic table has a special name for its columns, too. When a column goes from top to bottom, it's called a group. quoted from

12 Groups = Columns The elements in a group have the same number of electrons in their outer orbital. Every element in the first column (group one) has one electron in its outer shell. Every element on the second column (group two) has two electrons in the outer shell. As you keep counting the columns, you'll know how many electrons are in the outer shell. There are some exceptions to the order when you look at the transition elements, but you get the general idea.

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15 Families Periods Columns of elements are called groups or families. Elements in each family have similar but not identical properties. For example, lithium (Li), sodium (Na), potassium (K), and other members of family IA are all soft, white, shiny metals. All elements in a family have the same number of valence electrons. Each horizontal row of elements is called a period. The elements in a period are not alike in properties. In fact, the properties change greatly across even given row. The first element in a period is always an extremely active solid. The last element in a period, is always an inactive gas.

16 Other than periods and groups, the table is divided into families. From

17 ALKALI METALS very reactive metals that do not occur freely in nature malleable, ductile, good conductors of heat and electricity. can explode if they are exposed to water From

18 ALKLINE EARTH METALS metals very reactive not found free in nature From

19 TRANSITION METALS ductile and malleable, and conduct electricity and heat From iron, cobalt, and nickel, are the only elements known to produce a magnetic field.

20 RARE EARTH ELEMENTS many are man-made From

21 OTHER METALS are ductile and malleable are solid, have a high density, From

22 METALLOIDS have properties of both metals and non-metals some of the metalloids are semiconductors. This means that they can carry an electrical charge under special conditions. This property makes metalloids useful in computers and calculators From

23 NON-METALS not able to conduct electricity or heat very well very brittle Do not reflect light. From

24 HALOGENS "halogen" means "salt-former" and compounds containing halogens are called "salts" exist in all three states of matter From

25 NOBLE GASES do not form compounds easily Happy/Inert Elements (Full outer shells) From

26 Elements, Compounds, and Mixtures

27 What is an ELEMENT? oa substance composed of a single kind of atom. ocannot be broken down into another substance by chemical or physical means.

28 What is a COMPOUND? oa substance in which two or more different elements are CHEMICALLY bonded together.

29 What is a MIXTURE? otwo or more substances that are mixed together but are NOT chemically bonded.

30 Element, Compound or Mixture?

31 Element, Compound or Mixture?

32 Element, Compound or Mixture?

33 Element, Compound or Mixture?

34 Element, Compound or Mixture?

35 Element, Compound or Mixture?

36 Chemical Bonds Attraction between two or more atoms Interaction between valence electrons Ionic bonds Covalent bonds LecturePLUS Timberlake 36

37 Valence Electrons Electrons in the highest (outer) electron level Have most contact with other atoms Known as valence electrons Outer shells of noble gases contain 8 valence electrons (except He = 2) Example: Ne 2, 8 Ar 2, 8, 8 LecturePLUS Timberlake 37

38 Octet Rule An octet in the outer shell makes atoms stable Electrons are lost, gained or shared to form an octet Unpaired valence electrons strongly influence bonding LecturePLUS Timberlake 38

39 IONIC BONDING When an atom of a nonmetal takes one or more electrons from an atom of a metal so both atoms end up with eight valence electrons

40 Formation of Ions from Metals Ionic compounds result when metals react with nonmetals Metals lose electrons to match the number of valence electrons of their nearest noble gas Positive ions form when the number of electrons are less than the number of protons Group 1A metals ion 1+ Group 2A metals ion 2+ Group 3A metals ion 3+ LecturePLUS Timberlake 40

41 Ions from Nonmetal Ions In ionic compounds, nonmetals in 5A, 6A, and 7A gain electrons from metals Nonmetal add electrons to achieve the octet arrangement Nonmetal ionic charge: 3-, 2-, or 1- LecturePLUS Timberlake 41

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45 COVALENT BONDING When an atom of one nonmetal shares one or more electrons with an atom of another nonmetal so both atoms end up with eight valence electrons

46 Covalent bonding Fluorine has seven valence electrons F

47 Covalent bonding Fluorine has seven valence electrons A second atom also has seven F F

48 Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons F F

49 Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons F F

50 Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons F F

51 Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons F F

52 Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons F F

53 Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons Both end with full orbitals F F

54 Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons Both end with full orbitals F F 8 Valence electrons

55 Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons Both end with full orbitals 8 Valence electrons F F

56 Single Covalent Bond A sharing of two valence electrons. Only nonmetals and Hydrogen. Different from an ionic bond because they actually form molecules. Two specific atoms are joined. In an ionic solid you can t tell which atom the electrons moved from or to.

57 H Water Each hydrogen has 1 valence electron Each hydrogen wants 1 more The oxygen has 6 valence electrons The oxygen wants 2 more They share to make each other happy O

58 Water Put the pieces together The first hydrogen is happy The oxygen still wants one more H O

59 Water The second hydrogen attaches Every atom has full energy levels H O H

60 C Carbon dioxide CO 2 - Carbon is central atom you) Carbon has 4 valence electrons Wants 4 more Oxygen has 6 valence electrons Wants 2 more ( I have to tell O

61 Carbon dioxide Attaching 1 oxygen leaves the oxygen 1 short and the carbon 3 short C O

62 Carbon dioxide Attaching the second oxygen leaves both oxygen 1 short and the carbon 2 short O C O

63 Carbon dioxide The only solution is to share more O C O

64 Carbon dioxide The only solution is to share more O C O

65 Carbon dioxide The only solution is to share more O C O

66 Carbon dioxide The only solution is to share more O C O

67 Carbon dioxide The only solution is to share more O C O

68 Carbon dioxide The only solution is to share more O C O

69 Carbon dioxide The only solution is to share more Requires two double bonds Each atom gets to count all the atoms in the bond O C O

70 Carbon dioxide The only solution is to share more Requires two double bonds Each atom gets to count all the atoms in the bond 8 valence electron s O C O

71 Carbon dioxide The only solution is to share more Requires two double bonds Each atom gets to count all the atoms in the bond 8 valence electron s O C O

72 Carbon dioxide The only solution is to share more Requires two double bonds Each atom gets to count all the atoms in the bond 8 valence electron s O C O