Why do ionic compounds typically form between metals and non-metals?

Ionic compounds typically form between metals and non-metals due to the transfer of electrons from metals to non-metals.

In more detail, the formation of ionic compounds is fundamentally based on the principle of achieving a stable electronic configuration. Metals, which are located on the left side of the periodic table, have a few electrons in their outermost shell. These electrons are relatively loosely held by the nucleus due to their distance from it. Therefore, metals tend to lose these outer electrons to achieve a stable electronic configuration, similar to that of the nearest noble gas. This process results in the formation of positively charged ions, or cations.

On the other hand, non-metals, which are located on the right side of the periodic table, have more electrons in their outermost shell, which is nearly full. These elements tend to gain electrons to achieve a stable electronic configuration, again similar to that of the nearest noble gas. This process results in the formation of negatively charged ions, or anions.

When a metal and a non-metal react, the metal tends to lose electrons and the non-metal tends to gain these electrons. This transfer of electrons from the metal to the non-metal leads to the formation of ions. The resulting cations and anions are held together by strong electrostatic forces of attraction, forming an ionic compound. This is known as ionic bonding.

For example, in the formation of sodium chloride (NaCl), sodium (a metal) loses an electron to become a sodium ion (Na+), and chlorine (a non-metal) gains this electron to become a chloride ion (Cl-). The sodium and chloride ions are then held together by the strong electrostatic forces of attraction between them, forming the ionic compound sodium chloride.

In summary, the tendency of metals to lose electrons and non-metals to gain electrons, driven by the desire to achieve a stable electronic configuration, leads to the formation of ionic compounds between these elements.