Admin stuff

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Admin stuff

• OWLs Will be posted this afternoon
• Reading 3.3-3.4
• Test 2 you will receive email as soon as
  scores are available
• Memorization

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First ionization energies
Configuration of B, B Configuration of O, O
Periodic trends (1) Hardest to ionize elements
on right (2) Hardest to ionize elements on top
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Ionization energies

• A(g) - A(g) e-
• A(g) - A2 e-
• A2(g) - A3 e-

• 1st, 2nd, and 3rd IEs

• Provides evidence for stability of half / full
  subshells
• Same trends as we observed earlier for Z

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Electron affinities (Ch. 8-6)

• Electron affinity is the energy change on adding
  an electron to an atom.

• Electron affinities are also obtained in the gas
  phase.
• A(g) e- - A-(g)

DE electron affinity

• (Sometimes in literature sign of EA is reversed)

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Electron affinities

• Magnitudes of EA are small relative to IE
• Many atoms will not capture an extra e (EA0,
  unmeasurable)

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Ions and Ionic Compounds

• Pure elements occur in an electronically neutral
  form
• ( electrons Z protons)
• Ions occur when electrons are taken from one atom
  and moved to another
• Ions generally occur when two different types of
  elements are present

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Ions and Ionic Compounds
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Types of ions

• Cations
• Have a positive charge
• Have lost one or more electrons
• Examples include Na, Mg2, Al3
• Anions - - - - - - - - - - - - - - - - - - - - -
  - - - - - - -
• Have a negative charge
• Have gained one or more electrons
• Examples include F-, O2-, N3-
• Note that the number comes before the sign for
  the charges.

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Which elements form ions?

• All elements except certain noble gases
  chemically form stable ionic compounds
• All elements can be ionized by physics
  techniques (large voltages, ionizing radiation,
  etc.)
• A plasma occurs when most/all the electrons have
  be stripped away from atoms

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Which elements form which monoatomic ions?

• Metals tend to form cations while non-metals tend
  to form anions
• Charge is closely related to position in periodic
  table
• More than one charge may be possible for an
  element

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How to name ions

• Anions
• change suffix to -ide
• chlorine - chloride ion
• oxygen - oxide ion
• sulfur - sulfide ion
• phosphorus - phosphide ion
• selenium - selenide ion
• hydrogen - hydride ion

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How to name ions

• Cations
• Generically refer to cations by adding the word
  ion after the name of the element
• Examples silver ion, magnesium ion, etc.
• When metals are found with more than one
  oxidation state, the ionic charge is written out
  with roman numerals
• Examples Manganese(II) ion, Iron(III) ion,
  Titanium(IV) ion

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Name this ion

• chlorine ion
• chlorinide ion
• chloride ion
• chloride
• chlorine
• chlorine

Cl
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Name this ion

• calcide ion
• calcide(II) ion
• calcide(2) ion
• calcium ion
• calcium(II) ion
• calcium(2) ion

Ca2
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Name this ion

• oxide ion
• oxygen(II) ion
• oxygenide(II) ion
• ozone ion
• ozone(I) ion

O2-
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Name this ion

• iron ion
• iron(III) ion
• iron(3) ion
• iron cation
• iron(III) cation
• iron(III) cation

Fe3
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What is the charge on this ion?

• 4
• 3
• 2
• 1
• 0
• -1
• -2
• -3
• -4

carbide ion
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What is the charge on this ion?

• 3
• 2
• 1
• 0
• -1
• -2
• -3
• not enough info

lithium ion
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What is the charge on this ion?

• 3
• 2
• 1
• 0
• -1
• -2
• -3
• not enough info

copper ion