Metals
1.Shiny appearance.
2.They are solids at room temperature (except mercury).
3. High melting points
4.High densities
5.Large atomic radii
6.Usually, high deformation
7.Malleable
8.Ductile
9.Thermal conductors
10.They can conduct electricity.
11. They tend to lose electrons
On this periodic table, all the grey colored elements are metal. When reading a periodic
table, the metals on the left are most reactive and as we move along to the right the
metals get less reactivate, at the end the metals are not reactive. As the atomic number
increases their mass also increases. Some of the heaviest metals are synthetic (man made)
The research question
Is the reactivity of a metal related to the year it was discovered.?
Hypothesis
When looking at the periodic table. I think that the most
reactive metals can be hard to discover therefore they were
discovered later because if it’s most reactive then it can
easily react and combine with any other element that can
be found on Earth. The least reactive metals would be
easy to find in the elemental form since they react less and
would be discovered first. The discovery date will also
depend on humans and our knowledge. Some metals can
be hard to separate the metal itself from other elements,
therefore it can
affect the date of discovery. The metals that are easier to
separate will be discovered first.
The different groups of metals
Most reactive (Alkali Metals)
Alkali metals have one electron on the outer shell. This electron will leave the metal to form a pair with a new
element. Alkali metals react with water H20 and air O2 and all non-metals.
Cesium (Most reactive, and was discovered later)
Atomic Number: 55
Symbol: Cs
Atomic Weight: 132.90543
Discoverer: Gustov Kirchoff, Robert Bunsen
Discovery Date: 1860 (Germany)
Potassium
Atomic Number: 19
Symbol: K
Atomic Weight: 39.0983
Discovery: Sir Humphrey Davy 1807 (England)
Sodium
Atomic Number: 11
Symbol: Na
Atomic Weight: 22.989768
Discovery: Sir Humphrey Davy 1807 (England)
The different groups of metals
Most reactive (transition metals)
Zirconium
• Atomic Number: 40
• Symbol: Zr
• Atomic Weight: 91.224
• Discovery: Martin Klaproth 1789 (Germany); zircon mineral is mentioned in biblical texts.
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Yttrium
Atomic Number: 39
Symbol: Y
Atomic Weight: 88.90585
Discovery: Johann Gadolin 1794 (Finland)
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Rutherfordium
Atomic Number: 104
Symbol: Rf
Atomic Weight: [261]
Discovery: A. Ghiorso, et al, L Berkeley Lab, USA 1969 - Dubna Lab, Russia 1964
Word Origin: Named after Ernest Rutherford
Appearance: radioactive synthetic metal
The different groups of metals
regularly reactive
Technetium (Masurium)
Technetium is a silver, gray radioactive metal. It is sometimes seen as a gray powder.
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Atomic Number: 43
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Symbol: Tc
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Atomic Weight: 98.9072
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Discovery: Carlo Perrier, Emilio Segre 1937 (Italy) found it in a sample of molybdenum that had been bombarded with
neutrons; erroneously reported Noddack, Tacke, Berg 1924 as Masurium.
Bohrium (formerly Nielsbohrium)
radioactive synthetic metal, Bohrium is a man-made element. In 1976
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Atomic Number: 107
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Symbol: Bh
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Atomic Weight: [264]
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Discovery: Dubna (Russia) 1975 or Heavy Ion Research Lab (Germany) 1976
Word Origin: Formerly Ns, Nielsbohrium. Named in honor of Niels Bohr.
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Osmium
Atomic Number: 76
Symbol: Os
Atomic Weight: 190.23
Discovery: Smithson Tennant 1803 (England), discovered osmium in residue remaining when crude platinum was dissolved
in aqua regia
Properties: Osmium has a melting point of 3045 +/- 30 °C, boiling point of 5027 +/- 100°C
The different groups of metals
Gold/(soft, malleable, yellow metal)
Least Reactive
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Atomic Number: 79
Symbol: Au
Atomic Weight: 196.9665
Discovery: known since prehistoric time
Melting Point (°K): 1337.58
Boiling Point (°K): 3080
Gold is a good conductor of electricity and heat. It is not affected by exposure to air or to most
elements. Gold is used in coin and mainly jewelry. It is also used for dental work, plating, and
reflectors.
Copper
• Atomic Number: 29
• Symbol: Cu
• Atomic Weight: 63.546
• Discovery: Copper has been known since prehistoric time.
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It has been mined for more than 5000 years.
• Word Origin: Latin cuprum: from the isle of Cyprus, which is famed for its copper mines
• Properties: Copper has a melting point of 1083.4 +/- 0.2°C, boiling point of 2567°C
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Where its found: Sometimes copper appears in its native state. It is found in many minerals,
including malachite, cuprite, bornite, azurite, and chalcopyrite.
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Silver (silvery, ductile, malleable metal )
Atomic Number: 47
Symbol: Ag
Atomic Weight: 107.8682
Evaporation Heat (kJ/mol): 254.1
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Discovery: Known since prehistoric time.
Word Origin: Anglo-Saxon Seolfor or siolfur; meaning 'silver', and Latin argentum meaning
'silver'
Properties: The melting point of silver is 961.93°C, boiling point is 2212°C
Uses: The parts of silver have many uses. Sterling silver (92.5% silver, with copper or other
metals) is used for silver items and jewelry. Silver is used in photography, dental uses, solder,
brazing, electrical contacts, batteries, mirrors .
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AOI : Human Ingenuity
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This project Is related to Human Ingenuity. Science is not only around nature but also
humans. We learn about humans and nature together and how both can have effect on
Earth. This AOI relates to metals and my research question because, I learned that not only
the reactivity of the metal affects the year of discovery but also humans. It also depends on
humans and their knowledge. Humans can invent and create. They can come up with ideas
and as technology improves they come up with more ideas. Human experimentation is also
very important and by performing tests, it can help us with research which will increase our
knowledge and understanding of the world around us.
Conclusion
My hypothesis was correct as shown in the data. Metals such as copper, gold and
silver were discovered in pre-historic times. But the most reactive metals were only
discovered recently. For example, the very reactive alkali metals were discovered in
the 1800’s. Reactive transition metals like Zirconium was discovered in the year
1789. Yttrium was discovered in the year 1794 and the metal: Rutherfordium was
created and discovered in the year 1969. But in the regularly reactive group of
metals there is Bohrium which was discovered in the year 1975 and does not fit my
hypothesis. The metal doesn’t have to be the least reactive to be discovered first.
What can also affect the date of discovery is human knowledge. Some metals are
harder to separate from other elements. The metal Bohrium was discovered later
than the most reactive metals because it is a man made element. This element was
discovered later because the people didn’t have the knowledge and technology to
separate this element to create it. Bohrium was produced by exposing it to radiation.
On the opposite side, silver was discovered in the prehistoric times because people
learned how to separate silver from lead as early as 3000 B.C. Gold was also
discovered in the prehistoric times because it was the least reactive and didn’t react
with the Earth elements. Pure gold has a bright yellow color and does not oxidize in
air or water. These metals occur mostly in natural elemental forms as nuggets or
grains in rocks. But in some cases it occurs in minerals as gold compounds, usually
with tellurium.
Bibliography
• "Periodic Table - Interactive Periodic Table of the Elements." Chemistry Periodic Table, Chemistry Projects, and Chemistry Homework Help. Web.
23 Oct. 2011. <http://chemistry.about.com/library/blperiodictable.htm>.
• References (book): Los Alamos National Laboratory (2001), Crescent
Chemical Company (2001), Lange's Handbook of Chemistry (1952)