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Geology 311
Strong
tendency to
lose outermost
electrons
Earth Materials II: Geochemistry
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The Periodic Table groups elements
by similarities in their chemical properties.
Atomic number
Chemical symbol
Tend to share,
gain, or lose
electrons
Inert
(noble)
Strong
tendency gases
to gain
electrons
Transition elements
P f
Professor:
Steve
St
K
Kuehn
h
Course web site:
http://home.wlu.edu/~kuehns/Geo311/index.html
Lanthanides
Actinides
See: http://www.webelements.com/webelements/index.html
Nuclear and electron configurations of H and C
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Electron orbitals
Modified from Fig 2.2 Understanding Earth
Electrons and orbitals by period (row) of the periodic table
Brownlow Fig. 1-2
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Ionization potentials at opposite ends of the periodic table
U, Pu, etc.
Rb, Ag, etc.
C, O, etc.
Ca Fe,
Ca,
Fe etc.
etc
Na, Si, etc.
C, O, etc.
H, He
White, Chapter 1
Brownlow
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Overall distribution of 1st ionization potentials
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Ionic radii – vary by charge and period
What will happen if we
try and take away 2 e-?
White, Chapter 1
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Solar system elemental
abundances
White, Chapter 1
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Types of meteorites, a generalized overview
Carbonaceous
chondrites (a subcategory of stony)
appear to reflect
undifferentiated,
average solar system
material
Stony meteorite
with chondrules
Iron meteorite
with crystalline
texture
Stony-iron meteorite
How do we know this?
Brownlow
The sun’s composition is known from spectroscopy
The absorption and emission lines are characteristic of specific elements
and can be used to determine the composition of distant gases.
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Chondrite vs. solar abundances – What does this mean?
Brownlow
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In nuclear reactions that form
heavier elements, isotopes
matter: Start with different
isotopes = get different results
Why this pattern?
Atomic number = 1
Atomic weight = 2
Atomic number = 1
Atomic weight = 1
Atomic number = 1
Atomic weight = 3
Brownlow
Elemental distribution in the solar system
Modified from Fig 2.2 Understanding Earth
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The layered,
differentiated
Earth
White, Chapter 1
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Composition of the atmosphere
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Major components of clean, dry air include:
• Nitrogen (N) – 78%
• Oxygen (O2) – 21%
• Argon – 0.93 %
• Carbon dioxide
(CO2) – 0.036%
0 036%
Relative abundances
of the top 8 elements
Figure 1-6 Understanding Earth
• All other gases –
less than 0.1 %
• Plus variable
amounts of water
Earth Science - Tarbuck & Lutgens
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