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Carbon is the sixth element, with a ground-state electron configuration of 1s 2 2s 2 2p 2, of which the four outer electrons are valence electrons. Its first four ionisation energies, 1086.5, 2352.6, 4620.5 and 6222.7 kJ/mol, are much higher than those of the heavier group-14 elements.
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond as a form of carbon is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of electricity, and insoluble in water.
In diamond form, carbon is one of the costliest elements. The crystal structure of diamond is a face-centered cubic lattice having eight atoms per unit cell to form a diamond cubic structure. Each carbon atom is covalently bonded to four other carbons in a tetrahedral geometry.
Small amounts of natural gold have been found in Spanish caves used during the late Paleolithic period, c. 40000 BC. [1] The earliest gold artifacts dating to 4600 BC to 4200 BC were discovered at the site of Varna Necropolis, Bulgaria. [2] Recognised as an element by Guyton de Morveau, Lavoisier, Berthollet, and Fourcroy in 1787. [3] 6 Carbon
Having started with only diamond and oxygen, and produced a gas which contains only carbon and oxygen, Tennant had discovered that diamonds are made of carbon. Unaware of atomic theory at the time, scientists were unable to explain how carbon, already known to exist as one of the softest substances in the form of graphite , could also be the ...
It was recognised as an element by Guyton de Morveau, Lavoisier, Berthollet, and Fourcroy in 1787. [6] The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15]
Scientists have figured out how to grow synthetic diamonds in just 150 minutes—and that could be bad news for natural jewels.
Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure.. Allotropy or allotropism (from Ancient Greek ἄλλος (allos) 'other' and τρόπος (tropos) 'manner, form') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements.