CBSE Class 10 Answered
Covalent bond is formed by sharing of electrons between two atoms. Both the atoms involved in bond formation contribute electrons. eg Cl atom needs one electron to attain stability. Thus it shares an electron with another Cl atom.There is a shared pair of electrons between both the atoms leading to formation of Cl2. (in contrast to ionic bond where there is loss or gain of electrons). The bonded atoms are still neutral. Both the atoms have attained stability as have shared one electron with other atom.
In a covalent bond the shared pair is under the influence of nuclei of both bonded atoms.
If four electrons are being shared(two from each atom) there is formation of a double covalent bond eg. O2. And with three pairs being shared, we get a triple covalent bond eg. N2