Transcript Metals Unit - Landerson.net

Metals Unit
• Metals make up 84 of the 103 elements on a
standard periodic table…the elements above 103
are also metals, but they are relatively rare and
are man-made.
• Metals have a sea of free moving electrons that
give them properties of conductivity, malleability,
and ductility.
• Most all metals have a natural luster in their pure
form, although some form oxide layers that cause
them to be dull.
Abundance of Metals
• Aluminum is the most abundant metal on the
earth…it is the 3rd most abundant element in
the earth’s crust after oxygen and silicon.
• Iron is the second most abundant metal in the
earth’s crust, closely followed by calcium.
Abundance of Elements In the Earth’s
Crust
• 10 Most Abundant Elements in the Earth's Crust
• Source: CRC Handbook of Chemistry and Physics,
77th Edition
• Element Abundance
• Abundance
• percent by weight
• Oxygen
46.1%
• Silicon
28.2%
• Aluminum 8.23%
parts per million by weight
461,000
282,000
82,300
Aluminum
• Aluminum is the most abundant metal on Earth, but it has
had a small impact on man until the 1900’s.
• Aluminum is not found pure in nature and the process of
isolating aluminum was invented by Charles Joseph Bayer
in 1887….called the Bayer process…see below.(900oC)
• Bauxite ore (Al2O3) is 37-54% aluminum.
Aluminum Data Sheet
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Atomic Number 13
Atomic Mass 26.98 amu
Electron Config. 1s22s22p63s23p1 .
Density
2.70 g/cm3
Melting pt.
660.3oC
Heat of fusion 10.71 kJ/mol or .09929 kj/g
Reflectivity
92% visible/98% infrared
Conductivity
59% of copper/30% copper’s
density
• Al makes up 8% of the earth’s solid surface by
Aluminum Data Sheet
• Aluminum forms an oxide coating on the outside
that protects it from further oxidation.
• 33% of aluminum comes from recycled
aluminum…this saves 95% of the energy…you only
have to heat aluminum to 660 oC to melt and
recycle as opposed to over 900oC for purifying it
from Al2O3 ore.
• No known form of life uses aluminum salts in
metabolic processes and organisms tolerate Al well.
Copper Data Sheet
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Atomic Number 29
Atomic Mass 63.55 amu
Electron Config. 1s22s22p63s23p613d104s1.
Density
8.96 g/cm3
Melting pt.
1,084.6oC
Heat of fusion 13.26 kJ/mol
Reflectivity
30% blue light to 86% red light
Conductivity
The 2nd most conductive metal
94.6% as conductive as silver.
• Al makes up .0068% of the earth’s crust by weight.
Copper Data Sheets (cont’d)
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Alloys of copper
brass: copper + zinc
bronze: copper + tin
cupro nickel: copper + nickel
Together with cesium and gold (both yellow/gold)
and osmium (bluish) copper is only one of 4 metals
that are other than grey/silver.
• Copper can be 100% recycled, but recycled copper
has slight impurities which are difficult to remove
and cannot be used for electrical conductive uses,
but is fine for plumbing…copper can be joined easily
Top 4 Metals of Conductivity
Resistivity ρ (Ω•m) at 20 °C
1.
2.
3.
4.
Silver
1.59×10−8
Copper 1.68×10−8
Gold
2.44×10−8
Aluminum 2.82×10−8
σ Conductivity (S/m) at 20 °C
6.30×107
5.96×107
4.10×107
3.5×107
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Gold Data Sheets
Atomic Number 79
Atomic Mass 196.97 amu
Electron Config. Gold: Z:79 [Xe] 6s1 4f14 (exception)
Density
19.3 g/cm3
Melting pt.
1,064oC
Heat of fusion 12.5kJ/mol
Reflectivity
95%
Conductivity
The 3rd most conductive metal
65% as conductive as silver.
• Au makes up 3.1x10-7% of the earth’s crust by
weight.
Gold Price
• The current price of gold is $1224.30 per ounce.
•
http://www.austincoins.com/goldprices?mm_campaign=ded766d9b14132b905fbb47191e5350e&mm_replace=true&gclid=Cj0KEQjwstaqBRCT38DWpZjJotIBEiQAERS6_Od2I_IGVajWMT96eQhzid0jjOly
U1xQH1n7TG3wauwaAreP8P8HAQ
• Link to gold price history
Specific Heats of Some Substances
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Substance
Aluminum
Bismuth
Copper
Brass
Gold
Lead
Silver
Tungsten
c in J/gm K
0.900
0.123
0.386
0.380
0.126
0.128
0.233
0.134