Molecules and Covalent bonds

Covalent bonds are formed when two atoms share pairs of electrons, allowing both atoms to achieve a more stable electronic configuration, often resembling the noble gas configuration. Here’s a description of the formation of single covalent bonds in several molecule.

Here is a concise table summarizing the electron sharing in some simple covalent molecules:

H2 (Hydrogen Gas):

• In a hydrogen molecule (H2), two hydrogen (H) atoms come together to share one electron pair. Each hydrogen atom has only one electron in its 1s orbital. When they share their electrons, both hydrogen atoms end up with two electrons each, achieving the electron configuration of helium (He). Helium has two electrons and a full 1s orbital, making it stable.

Cl2 (Chlorine Gas):

• In a chlorine molecule (Cl2), two chlorine (Cl) atoms share one electron pair. Chlorine has 17 electrons in its ground state, and it needs one more electron to achieve the electron configuration of argon (Ar) which is stable with 18 electrons and a full 3p orbital. By sharing one electron pair, each chlorine atom completes its outer electron shell and achieves stability.

H2O (Water):

Water (H2O) consists of one oxygen (O) atom sharing two electron pairs with two hydrogen (H) atoms. Oxygen has 8 electrons in its ground state and needs two more electrons to achieve the electron configuration of neon (Ne) which is stable with 10 electrons and a full 2p orbital. Each hydrogen atom shares one electron pair with the oxygen atom, providing the oxygen atom the additional two electrons it needs to complete its outer shell. The result is that oxygen now has 8 electrons (like neon), and each hydrogen has 2 electrons.

CH4 (Methane):

• Methane (CH4) is composed of one carbon (C) atom sharing one electron pair with each of the four hydrogen (H) atoms. Carbon has 6 electrons in its ground state and needs four more electrons to achieve the electron configuration of neon (Ne), which is stable with 10 electrons and a full 2p orbital. By sharing one electron pair with each hydrogen atom, carbon attains the necessary four additional electrons, completing its outer electron shell. Each hydrogen atom also gains an electron in this process, resulting in each hydrogen having 2 electrons.

NH3 (Ammonia):

• Ammonia (NH3) consists of one nitrogen (N) atom sharing three electron pairs with three hydrogen (H) atoms. Nitrogen has 7 electrons in its ground state and requires three more electrons to achieve the electron configuration of neon (Ne), which is stable with 10 electrons and a full 2p orbital. By sharing three electron pairs with the hydrogen atoms, nitrogen acquires the necessary three additional electrons, completing its outer electron shell. Each hydrogen atom receives an electron in this process, resulting in each hydrogen having 2 electrons.

HCl (Hydrogen Chloride):

• Hydrogen chloride (HCl) is formed when one hydrogen (H) atom shares one electron pair with one chlorine (Cl) atom. Hydrogen has 1 electron in its ground state and needs one more electron to achieve the electron configuration of helium (He), which is stable with 2 electrons and a full 1s orbital. By sharing one electron pair with the hydrogen atom, chlorine attains the necessary electron, completing its outer electron shell. The hydrogen atom gains an electron in this process, resulting in the hydrogen having 2 electrons (like helium), and chlorine has 8 electrons (like argon).

In summary, the covalent bonding allows atoms to share electrons in pairs, resulting in each atom achieving a stable noble gas-like electron configuration. The table shows how this electron sharing occurs in some simple molecules.