chp 5 pg 122. a. history of the periodic table 1. mendeleev a.wanted to organize elements by...

31
The Periodic Law Chp 5 pg 122

Upload: marcus-jones

Post on 27-Dec-2015

215 views

Category:

Documents


0 download

TRANSCRIPT

  • Slide 1
  • Chp 5 pg 122
  • Slide 2
  • A. History of the Periodic Table 1. Mendeleev a.Wanted to organize elements by properties b.Left empty spaces for elements that hadnt been discovered c.Elements were discovered and fit in his spaces
  • Slide 3
  • Slide 4
  • 2. Moseley a.Arranged elements by number of protons b.Worked with what Mendeleev said
  • Slide 5
  • 3. Modern Periodic Table a. Changed many times before what we have now b. Periodic table arrangement of elements in order of their atomic #s so elements w/same properties are in the same column c. Noble gases 1) Took long time to discover 2) Dont react
  • Slide 6
  • d. Lanthanides atomic numbers 58 71 e. Actinides atomic numbers 90 103 f. Lanth and act, belong in periods 6 &7 in between families 3 and 4 1) Period horizontal row 2) Family (groups) a) Columns b) Same number of val. electrons c) Causes same properties
  • Slide 7
  • 1. Electrons of highest energy level give atoms properties (valence electrons) 2. Periods and Blocks of Periodic Table a. Period tells what energy level b. Families determine # of valence electrons
  • Slide 8
  • c. Blocks tells which sublevel is filled 1) s-block = groups 1 and 2 2) p-block = groups 13-18 (not helium) 3) d-block = group 3-12 4) f-block = lanthanides, actinides
  • Slide 9
  • Slide 10
  • 3. s-block elements a. Chemically reactive metals b. Family 1 = more reactive than 2 c. Alkali metals 1) Family 1 2) One valence electron 3) Lose electron easily 4) Silvery appearance 5) Very soft cut with knife 6) Not found as free elements 7) More reactive at bottom of table
  • Slide 11
  • d. Alkaline-earth metals 1) Group 2 2) 2 valence electrons 3) Harder, denser, and stronger than group 1 4) Higher melting points 5) Not free elements 6) Calcium: bones, limestone, marble MacGyver Na bomb http://www.youtube.com/watch?v=Q0ASFXacVK0
  • Slide 12
  • 4. Hydrogen and Helium a. Hydrogen 1) Doesnt have same properties as family 1 2) Used in ammonia (NH3) and fertilizers b. Helium 1) Not reactive 2) Only 2 electrons
  • Slide 13
  • Used H not He
  • Slide 14
  • 5. d-block elements (Groups 3-12) a. Transition metals b. Good conductors heat and electricity c. High luster d. Less reactive than families 1 & 2 e. Can exist as free elements Mercury: http://www.youtube.com/watch?v=gjR6ZJzXdIs&feature=relmfu
  • Slide 15
  • Slide 16
  • 6. p-block elements a. Valence electrons = family number minus 10 b. Has metalloids and nonmetals c. Halogens 1) Most reactive nonmetals 2) Family 17 d. Metalloids (semiconductor) 1) Both sides of zigzag 2) Brittle solids 3) Characteristics of metals and nonmetals
  • Slide 17
  • e. Noble gases 1) Group 18 2) Full outer shell (8 val. electrons) 3) Argon first discovered a) William Ramsey b) From Greek word argos meaning lazy or inactive
  • Slide 18
  • 7. f-block elements a. Lanthanides 1) Shiny 2) Used in color TV and monitors b. Actinides 1) Radioactive 2) 94 103 are only in labs
  • Slide 19
  • 1. Mixture of 2 or more elements of which at least one is a metal 2. Examples a. Sterling silver 1)Silver and copper 2)Resists corrosion and stronger than silver
  • Slide 20
  • b. Steel 1) Mix of iron, carbon, and sometimes manganese and nickel 2) Very strong c. Stainless steel 1) Steel and chromium 2) Resists rust
  • Slide 21
  • STERLING SILVERSTAINLESS STEEL
  • Slide 22
  • 1. Atomic Radii a. the distance between 2 nuclei of identical atoms bonded together
  • Slide 23
  • b. Gets smaller going to the right 1) More electrons and protons 2) Pull things together more c. Get larger going down a group
  • Slide 24
  • Slide 25
  • 2. Ionization Energy a. Electrons can be removed w/enough energy b. Ion atom with a charge c. Ionization anything that causes the formation of ions d. Ionization energy energy needed to remove electrons e. Low IE = high reactivity f. 2 nd electron takes more energy to remove than 1 st ; 3 rd more than 2 nd
  • Slide 26
  • Slide 27
  • 3. Electron Affinity a. Energy change that occurs when an electron is added to a neutral atom b. Atom will be unstable and lose the electron c. Halogens gain them rapidly d. Decreases down a group e. Increases going left to right across period
  • Slide 28
  • 4. Ionic Radii a. Cation positive ion 1) Loss of 1 or more electrons 2) Decrease in atomic radius; smaller electron cloud 3) Typically metals b. Anion negative ion 1) Adding 1 or more electrons 2) Increase in atomic radius 3) Typically nonmetals
  • Slide 29
  • 5. Valence Electrons (150) a. Electrons that are gained, lost, or shared are valence electrons b. Outermost electrons c. Found in completely filled orbits d. Determining number of valence electrons 1) Group 1 & 2 have 1 & 2 valence electron 2) Group 13-18 subtract 10 from group #
  • Slide 30
  • 6. Electronegativity a. How well an atom in a chemical compound attracts electrons b. Makes a higher concentration of electrons c. Decreases down a group d. Increases left to right across period
  • Slide 31