College Prep' Chemistry Chapter 5 p' 1

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College Prep. Chemistry Chapter 5 p. 1

• Mendeleevs Periodic Table he arranged the
  elements in his periodic table according to
  increasing atomic mass.
• He predicted the physical and chemical properties
  of missing elements by averaging the properties
  of the known elements. Late 1800s.
• Henry Moseley in 1913 he determined the nuclear
  charge (atomic number of the element). He
  arranged the periodic table by order of
  increasing atomic number. Periodic Law- The
  physical and chemical properties of the elements
  are periodic functions of their atomic numbers.

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College Prep. Chemistry Ch. 5 p. 2

• Modern Periodic Table- 7 horizontal rows
  periods
• Vertical columns groups or families, similar
  chemical and physical properties.
• Properties within a period change.
• Valence Electrons electrons in the highest
  occupied energy level of an elements atom,
  outer electron configuration, determines the
  chemical properties of the element.
• Representative Elements- valence electrons equals
  the group number. Groups 1-8 A (Main Group
  Elements) s and p sublevels are partially filled
• Core Electrons Inner Electrons Ex. Na Ne 3s1

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College Prep. Chemistry Ch.5 p. 3

• Metals- good conductors of heat and electricity,
  malleable, ductile, make up most of the periodic
  table. They have 1-4 valence electrons.
• Nonmetals upper right hand corner of the
  periodic table. Poor conductors, dull, brittle,
  only carbon (graphite) conducts.
• Metalloids have properties that are similar to
  metals and nonmetals, along the diagonal Ex.
  Si, semiconductors
• Noble Gases- Group 18 (8A), chemically inert
• Lanthanides- first row below, from atomic number
  58.
• Actinides-2nd Row below, radioactive elements,
  atomic number 90-103, synthetic elements.
• Section Review p. 137 1-5

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College Prep. Chemistry Ch. 5 p. 4

• Group 1A Alkali Metals, most reactive metals
  ns1 configuration Hydrogen 1s1 , separate
  properties than the alkali metals.
• Group 2 A- Alkaline Earth Metals, second most
  reactive group of metals ns2 configuration
• Group 7A Halogens, F, Cl, Br, I, most reactive
  nonmetals ns2np5
• Group 8 A Noble Gases, Inert, Ne, Ar, Kr, Xe,
  He, s and p sublevels are filled. ns2np6 He
  1s2
• Transition Elements outermost electrons are in
  the d orbitals. Ex. Mn Ar 4s23d5 d block
  metals
• Inner Transition Metals outermost electrons are
  in the f orbitals. U Rn 7s26d15f3 Sample
  Problem A p. 143, Sample Problem B p. 146
• Practice p. 143 1,2, Practice p. 146 1,2

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College Prep. Chemistry Ch. 5 p. 5

• s block Groups 1A, 2A, He
• p block Groups 3A-8A (13-18) Main Group
  Elements Group 17, Halogens, most reactive
  nonmetals, gain 1 e- to get to a Noble gas
  configuration.
• d block Group B, Transition metals, 1 less
  than the period number
• f block Group B Inner Transition metals, 2
  less than the period number. Sample C, D p.
  148, Practice p. 148 1,2 Practice p. 149 1,
  Section Review p. 149
• The energy needed to remove an electron from a
  gaseous atom is called the Ionization Energy.
  Ex. K ? K e-
• Group Trends Ionization Energy decreases as you
• Move down a group. Size of the atom increases.
  Electrons are further from the nucleus, more
  weakly P. 155

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College Prep. Chemistry Ch. 5 p. 6

• Held, removed easily.
• Sample Problem F, p. 156
• Practice p. 156 1
• Periodic trends in ionization energy- ionization
  increases as you move from left to right across
  the period. As you move towards the right, there
  is a greater attraction of the nucleus for its
  outer electrons. Electrons are less likely to be
  lost.
• Electron Affinity ability of an atom to attract
  electrons to itself. Positive ions- cations,
  Negative ions are called anions. Valence
  electrons- outer shell electrons that are lost or
  gained. Metals tend to form cations, nonmetals
  form anions.

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College Prep. Chemistry Ch. 5 p. 7

• Electronegativity is the tendency for atoms of
  the element to attract electrons when they are
  chemically combined with another element. Same
  trends as electron affinity p. 161 chart
• F has the highest electron affinity, Cs has the
  lowest electron affinity. Noble Gases- no
  affinity for electrons.
• Periodic Trends Electron Affinity increases
  from left to right. Nonmetals attract electrons
• Group Trends- Electron Affinity increases from
  bottom to top. Larger atoms tend to lose
  electrons
• Sample Problem G p. 162, Practice p. 162-3 1

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College Prep. Chemistry Ch. 5 p. 8

• Not gain them. Electrons are further from the
  nucleus, more weakly held.
• Periodic Trends in Atomic Size X-Ray
  diffraction is used to determine size of solid
  atoms.
• Atomic Radius half the distance between the
  nuclei of two like atoms.
• Group Trends- Atomic size increases as you move
  down a group on the periodic table. You add more
  p, n, e, and energy levels overall.
• Atomic Size decreases as you move from left to
  right across a period.

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College Prep. Chemistry Ch. 5 p. 9

• As more electrons are added to the same energy
  level, they are pulled in tighter to the nucleus
  (with increasing nuclear charge).
• Sample Problem E p. 152, Practice p. 152 , 1-3
• Properties of the d-block elements vary with less
  regularity than the main-group elements. Their
  atomic radii generally decrease across a period.
• Ionization Energy and electronegativity also
  shows the same trends for the d-block.
• D-block elements remove electrons from the outer
  s shell before d electrons are removed from the
  outer shell.

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College Prep. Chemistry Ch. 5 p. 10

• Fe Ar 4s23d6 Fe2 Ar 3d6
• Fe3Ar3d5
• D-block elements commonly form 2 ions. Cu forms
  1 and 2. Ag forms 1. Cr forms 2 and 3, 6
• Cations are smaller than their neutral atoms,
  anions are larger than their neutral atoms.
• Electrons in the outermost shell available to be
  lost, gained or shared in the formation of
  chemical compounds are called Valence electrons.
• Section Review p. 164 1-3 (skip 4)
• P. 166-167 1,2,4,8,9,11,13-15,17,18,19, 20-23,
  25-29, 31, 32, 34-38