Free Radical | Lone Pair | Bond Pair |
---|---|---|
Homolytic bond cleavage generates two free radical species. A free radical is an atom carrying an unpaired electron, denoted as A. (atom symbol A with a dot for an electron on the superscript). | The valence electrons of an atom that did not participate in any covalent bond formation reaction exist as a lone pair. However, not all nonbonding electrons are lone pairs. It is denoted as two dots for two electrons above the atom’s symbol A.. | The valence electrons of an atom that took part in covalent bond formation are called the bond pair. A bond pair is shown as a dash holding two atoms, like Cl-Cl for the Cl2 molecule. A covalent bond linkage may also be denoted in Lewis structures using two dots for two electrons (Cl..Cl for Cl2 molecule). |
The free radical species is electron-deficient. | Amongst the p-block elements forming covalent bonds, Nitrogen, Oxygen, and Halogens have one, two, and three pairs. | Atoms form covalent bonds by sharing their valence electrons so that each atom forming the bond attains octet electron configuration in its outermost valence shell. So, the bond pair of electrons are indicative of the stability. |
They are unstable with a very short life span. | Lone pairs are nucleophilic in nature, except the halogen lone pairs. | If the bond pair of electrons is part of a polar covalent bond, they may participate in chemical reactions. A bond pair linked to highly electropositive metals like Boron, Aluminum, or Lithium can act as nucleophiles in reactions. |
They quickly undergo addition reactions. | They can undergo covalent bond formation reactions with an electron-deficient counterpart. | A bond pair of electrons can take part in covalent bond breaking and bond forming reactions. |
Related Reading – Free Radicals, Lone Pair, Bond Pair.