Download Mickey`s Mineral Part

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Mickey's Mineral part:
<define mineral, elements in earth (amount & size), how atoms arrange
themselves into minerals>
1. Mineral = A naturally occurring homogeneous solid with a definite (but
generally not fixed) chemical composition and a highly ordered atomic
arrangement, generally formed by inorganic processes.
<overhead & models Au & Halite & muscovite & amphibole>
2. Elements (in earth's crust: 20 miles continent
8 miles ocean)
<example" 10 O's & 10 H's -> 50 % O
or weight % 10 O's * 16 + 10 H's * 1 = 170
or 160 / 170 = 94% O>
- by weight %
oxygen (46%, O)
silicon (28, Si)
aluminum (8, Al)
iron (5, Fe)
calcium (4, Ca)
sodium (3, Na)
potassium (3, K)
magnesium (2, Mg)
99 %
- volume %: O = 96%
weight vs size
* atomic weight, directly related to atomic number
O = 16 & Si = 28
* atomic size is related to number of electrons
O = 0.7, O2- = 1.4A
Si = 1.2, Si4+ = 0.4A
<model kits>
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A = 1 * 10-10 m
If an atoms radius = 0.5 A:
how many atoms in a meter = 1 * 1010
how many atoms in a mm = 1 * 107
how many atoms in a mm2 = 1 * 1014
how many atoms in a mm3 = 1 * 1021
3. Atomic arrangement = crystal structure
* ions charge balance
* ions fit together
- what elements? (Si & O)
- Make charge balance (i.e., ratio of Si to O)?
SiO2 -> quartz (12 % of crust 20 miles land 8 miles o)
- Add Al to SiO2 ->feldspars (51 %)
- What is the shape of SiO4?
(mixed ionic & covalent)
- What is the shape of H2O in ice (a mineral)?
(mixed covalent & "ionic")
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etc: (handback test, go over & points & midterm, answer ?
(Bob & light
(Steve & pH
B. water chemistry kits & Introduction to minerals
1. Test kit results (get values, get more today)
pH
O2
CO2
hardness = amount of (Mg & Ca) in water
grains / gallon -> ppm (x 17.1)
ppm story & percents (pph)
1 in 1,000,000
10 in 1,000,000
......etc.
1,000,000 in 1,000,000 = 100%
<prove> 1 ppm = 1 mg/L (1 ml H2O = 1 g)
hydration spheres
Na & K = 4
Ca & Mg = 12
draw hydration spheres for each
? how does this effect H2O as a solvent?
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2. regulations (in Water Quality Factors...
set based upon several things
taste, smell, animals studies,
EPA standards (mg/L) = ppm (enforced)
As
0.05
1.8
Ba
1.0
400
Cd
0.010
0.2
Cr
0.05
100
Pb
0.05
13
Mg
150.3
20,900
Hg
0.002
0.08
Se
0.01
0.05
Ag
0.05
0.07
Zn
5.0
70
EPA standards (mg/L) = ppm (nonenforced)
Cl
250
130
Cu
1
55
Fe
0.3
50,000
Mn
0.05
900
<handout compositions & find "background for above>
some details on groundwater
<given granite & basalt which do you want a well in>
compare to elements in earth's crust
"minerals" vs minerals
C. Mineral classification
1. chemical classification
* minerals are classified on their main anion or anionic complex
ion = charged atom (O2-, Si4+
anion = negative ion (O2-, Clpolyatomic anions = negative group (SiO4)4- (PO4)3cation = positive ion (Si4+, Al3+
* ions combine to form minerals, such that the charges sum to zero
examples major mineral groups
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oxides: O2-: hematite, Fe2O3
hydroxides: (OH)-: gibbsite, Al(OH)3
100,000 -> 0.80 / lb
sulfides: S"-": pyrite,
FeS2
sulfates: (SO4)2-: gypsum, CaSO4.2H2O
phosphates: apatite & pyromorphite (Cl) (Pb ex)
carbonates: (CO3)2-: calcite, CaCO3
silicates: (SiO4)4-: a bunch! -> 93%
solubility - dissolving (more to less)
PbSO4, Pb(OH)2, PbCO3, Pb5(PO4)3(Cl), PbS
3.6*10-4 to 8.4*10-15 mol/l
2. structure classification
crystal structure = arrangement of atoms in the unit cell <overheads,
computer>
unit cell = smallest building block of a mineral
* anions & cations fit together as a result of sizes
(recall balls & Si & O)
<ball thing, with tet & octahedral>
Silicates: based on polymerization of the silicate tetrahedron
polymerization = joining like elemental groups
silicate tetrahedron = 1Si & 4O in with Si in center and Os at corners of a
tetrahedron (= pyramid)
build quartz
SiO2 -> feldspars
depolymerize -> sheets, chains, single
Earth's crust composition
feldspars (51%)
quartz (12%)
pyroxenes (11%)
amphiboles (5%)
micas (5%)
clays (5%)
other silicates (3%)
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nonsilicates (8%)
* and Pressure & Temperature conditions
thermodynamics
phase = a material with specific chemical & physical properties (= some
observable or measurable aspect)
Phase diagrams
vapor C
liquid C
graphite
T
diamond
P
<show models of graphite & diamond>
polymorphs = minerals with same chemistry, but different structure
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3. mineral names
* after places:
muscovite: used in Muscovy (Old Russia)
amosite: asbestos mines of South Africa
* on appearance:
mica: Latin micare, to shine
chrysotile: (Greek for golden fiber)
* on chemistry:
natrolite
* after people:
biotite: French Physicist J.B. Biot
<4000 minerals & Thesis>
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