Atomic Structure and the Periodic Table

Transcription

1 Structure and the

2 Structure Atoms are made of three particles: 1. Protons = positive 2. Neutrons = neutral 3. Electrons = negative The protons and neutrons are in the center of the atom (the nucleus) Electrons buzz around in a cloud around the nucleus

3 Structure

4 Different kinds of atoms make different elements Elements are organized in the Printed on a are several important pieces of information

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6 A lot of thought went into how the is organized They are arranged in order of number of electrons Columns (groups) have similar chemical and physical properties Also have same number of valence electrons Rows (periods) have the same number of electron layers Elements are also arranged by how metallic they are Metals to the left, non-metals to the right

7 Metalloids

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10 Symbol B Number Protons Neutrons 6 Electrons Mass

11 Symbol Number B Protons Neutrons 6 Electrons Mass

12 Symbol Number Protons Neutrons B 6 Electrons Mass

13 Symbol Number Protons Neutrons Electrons B 6 Mass

14 Symbol Number Protons Neutrons Electrons Mass B 6

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16 Symbol Number Protons Neutrons Electrons Mass 24

17 Symbol Number Na Protons Neutrons Electrons Mass 24

18 Symbol Number Protons Na Neutrons Electrons Mass 24

19 Symbol Number Protons Neutrons Na 13 Electrons Mass 24

20 Symbol Number Protons Neutrons Electrons Mass Na 13 24

21 Symbol Number Protons Neutrons 37 Electrons Mass

22 Symbol Ga Number Protons Neutrons 37 Electrons Mass

23 Symbol Number Protons Neutrons Ga 37 Electrons Mass

24 Symbol Number Protons Neutrons Electrons Ga 37 Mass

25 Symbol Number Protons Neutrons Electrons Mass Ga 37 68

26 Na Ga 13 68

27 Na Ga Y

28 Na Ga Y 39 Cu

29 Na Ga Y 39 Cu Tc

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31 Na Ga Y 39 Cu Tc

32 Na Ga Y 39 Cu Yb Tc

33 Na Ga Y 39 Cu Yb Ac Tc

34 Na Ga Y 39 Cu Yb Ac Tc

35 Na Ga Y 39 Cu Yb Ac Tc Tl

36 Na Ga Y 39 Cu Yb Ac Tc Tl Fm

37 Na Ga Y 39 Cu Yb Ac Tl Fm 0 29 Tc

38 Na Ga Y 39 Cu Yb Ac Tl Fm 0 29 Tc

39 Na Ga Y 39 Cu Yb Ac Tl Fm Tc Sg

40 Structure

41 Structure Let s break that down a bit. The classic model of an atom (the Bohr model) has protons and neutrons in the middle, surrounded by circling electrons

42 Structure In the Bohr model, electrons are stuck in their orbits unless something pushes them out These orbits are called shells, or energy levels Each shell can only have certain a certain number of electrons

43 Structure Shells on the

44 Structure The outermost shell contains special electrons called valence electrons These electrons are very important because they determine how reactive the atom is A full shell means the atom cannot react

45 Structure Valence electrons on

46 Structure What if an electron is forced out of its orbit? Let there be light! An electron will stay in a higher, excited orbit as long as something is forcing it to When that force stops, the electron returns to its original (ground) place and releases light

47 Structure We now know that electrons do not have to be within Bohr s orbits Electrons are most likely found in these orbits They really could be anywhere Rather than buzz around like planets, they float randomly forming a cloud

48 Structure STORY TIME!!!! Too simple??? OK.

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50 Structure Let s review. Element Name Element Symbol Number Protons Electrons Neutrons Metal, nonmetal, metalloid B Mass 89 metalloid

51 Structure Lewis Dot Diagrams/Structures Show how many valence electrons an atom has They show us if an atom's outer shell of electrons is full, or if it could bond with other atoms

52 Structure Lewis Dot Structures Let's try to draw a Lewis Dot Structure for Boron What is Boron s Symbol How many TOTAL electrons does boron have? How many of these are valence electrons? a. When placing the valence electrons, start at the top and go around, placing one electron above, one to the right, one to the left, and one below

53 Structure Lewis Dot Structures Let's try to draw a Lewis Dot Structure for Nitrogen What is nitrogen s Symbol How many TOTAL electrons does nitrogen have? How many of these are valence electrons? a. We use the same pattern to draw the electrons, but we have an extra now. Place it next to the electron at the top (to form a pair)

54 Structure Lewis Dot Structures Let s try to draw a Lewis Dot Structure for Krypton What is krypton s Symbol How many TOTAL electrons does krypton have? How many of these are valence electrons?

55 Structure Lewis Dot Structures Each table group will be assigned a group (column) of elements Draw a Lewis Dot Structure for every element in that group Be ready to report any patterns you see

56 Structure Lewis Dot Structures Each table group will be assigned a family (row) of elements Draw a Lewis Dot Structure for every element in that family Be ready to report any patterns you see

57 Structure Lewis Dot Structures Which elements are least reactive? Why? Which elements are most reactive? Why?

58 Structure

59 Structure

60 Structure

61 Structure Review Exit Ticket 1. What is the Bohr Model? What does it look like? 2. What is a physical property? 3. What is a chemical property? 4. Name a physical change.. Name a chemical change. 6. How is a pure substance different from a mixture. a. Compare and contrast a pure element and a compound b. Compare and contrast a heterogenous and a homogeneous mixture