Covalent BondingA covalent bond may be defined as the bond formed between two atoms when they complete their nearest inert gas configuration by sharing at least one electron with the other atom.
The covalent bond is generally represented by placing a small line between the combining atoms.
Example : H + H ------> H - H
Single Covalent Bond
Example : Formation of O2.
---(double covalent bond or O = O)
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Oxygen atom has six electrons in its outermost shell. It needs two electrons to complete its octet and attain the configuration of neon. Hence, two oxygen atoms combine by sharing two pairs of electrons between them and form a covalent molecule.
Triple Covalent BondIn case both the combining atoms are short of three electrons in their nearest noble gas configuration, they share three pairs of electrons and are said to possess a triple bond.
Nitrogen atom has five electrons in its outermost shell. It needs three electrons to complete its octet and attain the configuration of the inert gas neon. Hence, two nitrogen atoms combine by sharing three pairs of electrons between them and form a stable covalent molecule.
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