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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.Low ionization energies 7.Low electro negativities 8.Usually , high deformation 9.Malleable 10.Ductile
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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.Low ionization energies 7.Low electro negativities 8.Usually, high deformation 9.Malleable 10.Ductile 11.Thermal conductors 12.They can conduct electricity.
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.
The research questionIs 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 its 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 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 effect the date of discovery. The metals we know how to separate can be discovered first.
The different groups of metalsMost reactive Zirconium • Atomic Number: 40 • Symbol:Zr • Atomic Weight: 91.224 • Discovery: Martin Klaproth 1789 (Germany); zircon mineral is mentioned in biblical texts. • Yttrium • Atomic Number: 39 • Symbol: Y • Atomic Weight: 88.90585 • Discovery: Johann Gadolin 1794 (Finland) • 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 metalsregularly reactive Technetium (Masurium) Technetium is a silver, gray radioactive metal. It is sometimes seen as a gray powder. • Atomic Number: 43 • Symbol:Tc • Atomic Weight: 98.9072 • 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 • Atomic Number: 107 • Symbol:Bh • Atomic Weight: [264] • Discovery:Dubna (Russia) 1975 or Heavy Ion Research Lab (Germany) 1976 Word Origin: Formerly Ns, Nielsbohrium. Named in honor of Niels Bohr. • 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 metalsLeast Reactive Gold/(soft, malleable, yellow metal) • 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. • 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 • Where its found:Sometimes copper appears in its native state. It is found in many minerals, including malachite, cuprite, bornite, azurite, and chalcopyrite.
Silver (silvery, ductile, malleable metal ) • Atomic Number: 47 • Symbol: Ag • Atomic Weight:107.8682 • Evaporation Heat (kJ/mol): 254.1 • 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 .
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 Zirconium was discovered in the year 1789. Yttrium Was discovered in the year 1794 and the metal: Rutherfordium was discovered in the year 1969. But in the middle group of metals there is a metal Bohrium which was discovered in the year ) 1975 and this metal is not the most reactive metal. The research question was (what affects the date of discovery). The metal doesn’t have to be the least reactive to be discovered first. What can also affect the date of discovery is humans, 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, which was a mix of bismuth-209 with ions of chromium-54. On the opposite side, Sliver 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 Pure gold has a bright yellow color which it keeps without oxidizing in air or water. The metal occurs mostly in natural, uncompounded form as nuggets or grains in rocks, in veins and in alluvial deposits. 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)