Understanding the Basics
* Hydrogen (H): Has 1 proton and 1 electron. It needs 1 more electron to achieve a stable, full outer shell.
* Chlorine (Cl): Has 17 protons and 17 electrons. It needs 1 more electron to achieve a stable, full outer shell.
The Covalent Bond Formation
1. Sharing Electrons: Hydrogen and chlorine each have one electron in their outermost shell. To become stable, they share these electrons. This shared pair of electrons now counts towards both atoms' outer shells, making each atom effectively have a full outer shell.
2. Formation of the Molecule: The shared electron pair creates a strong attraction between the hydrogen and chlorine atoms, forming a covalent bond. This bond is represented by a single line in a structural formula (H-Cl).
3. Polarity: While the bond is covalent, it's not perfectly equal. Chlorine is much more electronegative than hydrogen, meaning it attracts the shared electrons more strongly. This creates a partial negative charge (δ-) on the chlorine atom and a partial positive charge (δ+) on the hydrogen atom. This makes the H-Cl bond a polar covalent bond.
Summary
The covalent bond between hydrogen and chlorine is formed by the sharing of electrons, creating a stable molecule of hydrogen chloride (HCl), also known as hydrochloric acid. The sharing is not perfectly equal, leading to a polar bond.
