Weil 1Copper is one of the first elements known to man. Due to its characteristic red color, copper is easily identifiable. In ancient times, copper could be found in the soil in its free state, without any interaction with other substances. Copper and its compounds have many uses in today's society. Copper has many chemical properties that make it unique. The atomic number of copper is 29. An atomic number is a measure of the amount of protons in the nucleus of an atom. Protons are subatomic particles, which have a positive charge. The atomic mass of copper is 63,546. Atomic mass is a measure of how many neutrons and protons there are in an atom. Neutrons are uncharged subatomic particles. Therefore, using the atomic mass and atomic number of copper, we can determine that it has 29 protons and 35 neutrons. Copper is a transition element and is found in column eleven of the periodic table. This means it has 11 electrons in its valence shell. The valence shell of an atom is the last shell of electrons. Copper is a metal found in period 4 of the periodic table. Other key properties include the density of 8.96 grams/centimeters3. Density is a measure of mass per unit volume in a substance. Copper has a melting point of 1083.3 degrees Celsius. The melting point of a substance is the temperature at which a solid changes to a liquid. Furthermore, the freezing point of copper is 2567 degrees Celsius. The freezing point of the substance is the temperature that a liquid turns into a solid. There are also many physical properties of copper including conductivity, malleability, ductility and corrosion resistance. Conductivity is the ability to conduct electricity. Silver is the single best conductor of electricity, but it is too expensive. Pure copper is a better electrical conductor than copper alloys, due to the impurities present in the alloys. Copper is also Weil 2 very malleable. Malleability is the ability to be easily molded. Copper does not break when hammered, stamped, forged, or spun into unusual shapes. Copper can be shaped both hot and cold. In addition to being easily molded, copper is subject to duties. Ductility is the ability to be drawn into thin threads without breaking. When heated, copper becomes very... half the paper... its red color is due to the iron. The other substance, hemocrianin, is the same as hemoglobin, except it uses copper instead of iron. So it has a blue color, instead of red. Examples of animals that contain hemocrianin are crustaceans. Copper is very abundant in nature. The metal is in the top quarter of the abundant elements in the earth's crust. A small part is also found in sea water. Copper is considered Weil 4 worldwide; fifty nations mine it today. Some include Albania, Argentina, Peru, Russia, Zambia and many others. The largest copper miners are Chile and the United States. Other major producers include Canada, Australia and Indonesia. In the United States, major producing states include Arizona, Utah, Montana, and Nevada. Copper is essential to modern society. Its uses are numerous and essential for many animals. Since the discovery of copper, it has been an integral part of industry, art and agriculture. Today's uses would not be possible if it were not for discoveries many, many years ago.