When a pair of electrons is shared between two atoms, the bond formed is called (a) a single covalent bond, (b) a double covalent bond, (c) a triple covalent bond, (d) an ionic bond.
The Correct Answer and Explanation is:
Correct answer: (a) a single covalent bond
Explanation:
A covalent bond is a type of chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms forms a molecule.
When only one pair of electrons is shared between two atoms, the resulting bond is known as a single covalent bond. This type of bond is the simplest form of covalent bonding and typically occurs between nonmetallic elements. A well-known example is the hydrogen molecule (Hâ‚‚), where each hydrogen atom contributes one electron to form a shared pair. This shared pair holds the two hydrogen atoms together in a stable arrangement.
A double covalent bond involves the sharing of two pairs of electrons, and a triple covalent bond involves the sharing of three pairs of electrons. These types of bonds are stronger and shorter than single bonds, but they are not the result of sharing only one pair of electrons.
On the other hand, an ionic bond is fundamentally different. It involves the transfer of electrons from one atom to another, usually between a metal and a nonmetal. The atom that loses an electron becomes a positively charged ion (cation), and the atom that gains an electron becomes a negatively charged ion (anion). These oppositely charged ions attract each other to form an ionic bond.
To summarize, when exactly one pair of electrons is shared between two atoms, the bond formed is called a single covalent bond. This type of bond is typical in many simple molecules and is essential to the structure of many compounds in chemistry and biology.
