Covalent bonds are a class of chemical bonds where valence electrons are shared between two atoms, typically two nonmetals. The formation of a covalent bond allows the nonmetals to obey the octet rule and thus become more stable.
The answer is 1s2 2s2 2p6
<span>In crystallography, the terms crystal system, crystal family, and lattice system each refer to one ... In total there are seven crystal systems: triclinic, monoclinic, orthorhombic, ..... A polar crystal possess a "unique" axis (found in no other directions) such ... lattices in three dimensions; each can apply in one lattice system only.</span><span>
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