Study of Metals

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University of Balamand
Faculty of Engineering
Department of Chemical Engineering
Chemical Engineering Lab
CHEN 215

Title: Study of Gold metal
Date: 14/01/2013
Submitted to: Dr Sami Habib
Submitted by: Jamil Mahfoud (A1010659)

I- General introduction about metals:
a- Historical background
Back to 6000 BC, process metallurgy is known as one of the oldest applied sciences. Despite that the form of metals was very basic but it has a big impact on the society because of its wide uses especially as tools for agriculture or hunting and even as artistic styles later on. There are 86 known metals so far that were discovered by time. From the first metal "Gold" discovered at 6000 BC, only 7 metals were known at antiquity "gold, copper, iron, lead, mercury, silver and tin". Later on metals were combined into alloys like bronze that is formed by a combination of copper and tin. Platinum and zinc are one of the few discoveries of metals before the industrial age where an important development occurs for a purer smelting, hotter furnaces and a greater control of alloys. Alchemy was a chemical philosophy in order to turn basic metals to gold. It began in the medieval Arab world and the goal was to turn lead to gold. For this aim, a lot of techniques were developed and used till today. Alchemists in the early Islamic practitioners created specific laboratories and developed lot of processes and procedures in order to accomplish the formation of gold from other metals.

Graph.1: The evolution of metals

The graph above shows an explosion in the discovery of metals after 1700 where science began to expand due to some discoveries by many scientists such as Joseph Priestly (discovery of oxygen), Henry Cavendish (hydrogen), and later on Cavendish and Benjamin Franklin innovation in electricity that was a big push for a better purifying tool for scientists that came after. As people demands increase in buildings, railroads, and bridges, iron and steel were one of the most used metals since the invention of the first cheap method for producing steel in 1855 by Henry Bessemer. Moreover, during the first and second world war in 20th century, the uses of metals like steel reach an extreme peak where aviation, tanks and weapons were mainly produced from steel until the end of the world war 2. Later on, the proliferation of power transmission and electronics rely on the use of metals. Copper and aluminum became more desirable due to their high conductivity of electricity and gallium and indium for a high electronics performance. b- Definition:

According to freedictionary.com, metal it's an object made of metal or an alloy of two or more metals. In general they consist of a category of electropositive elements. They can be melted or fused according to different temperatures applied.

Table.1: periodic table of metals

In the periodic table above, the first column of elements (Group 1) has the name alkali metals except hydrogen that consist as a part of noble gas, the group 2 elements are called the alkaline earth metals and from group 3 to 12, we called them transition metals while the ones that lies under the stairs line after group 12 are called other metals. It's important to know that silicon, germanium, arsenic, antimony, and tellurium are metalloids or semimetals that have both electro negativities and ionization energies between those metals and non metals. Their reactivity depends on properties of other elements in reaction and they often make good semiconductors.

II- General properties of metals

Hardness:

Fig.1: metals are solid

The figure above indicates that all metals have high density and they are solids at room temperature except mercury which is liquid heavy metal with toxic properties. "Hydrargyria" or "mercurialism" is a disease caused by the exposure of mercury on any human tissue....
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