INTRODUCTION. Copper was the first metal to be used by humans
Copper was the first metal to be used by humans. Today, it's the second most consumed metal, after iron. Copper was found first in Cyprus. That's why it takes its name from the Latin word Cuprum, meaning the island of Cyprus. The relative atomic mass of copper is 63.54 g/mol. Copper is a very soft metal with a characteristic red color. It is the lightest inert metal with a density of 8.92 g/cm3. It melts at 1084.6°C and boils at 2927°C. After silver, it is the second best conductor of electricity. The extensive use of copper makes it the second metal in commercial importance, after iron. The chief use of copper is in the production of all types of electrical wiring. Copper is also used in the production of alloys. Some important alloys are: brass (Cu, 60-82%; Zn, 18-40%), bronze (Cu, 70-95%; Zn, 1-25%; Sn, 1-18%), aluminum bronze (Cu, 90-98%; Al, 2-10%)
OCCURRENCE
In spite of the wide use of copper, it is not abundant in the earth’s crust. In nature it is found as compounds and in elemental form. The most important copper minerals are chalcopyrite (copper pyrite), chalcocite, agurite, cuprite and malachite.
USES
Most copper is used in the production of copper wire and plates. It's vaporized easily in a vacuum, so it is used in mirrors which reflect infrared rays. It produces strong alloys with gold. In the production of bronze and brass it is used in different ratios. Its soluble compounds are poisonous. Copper (I) oxide a pigment, is used to produce red colored glass.
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