In the bond formation between magnesium and oxygen, what happens to the electrons?

In the bond formation between magnesium and oxygen, electrons are indeed lost and gained. Magnesium, which is an alkaline earth metal, has two electrons in its outer shell. To achieve a stable electronic configuration, magnesium tends to lose these two electrons, transforming it into a positively charged ion (Mg²⁺).

On the other hand, oxygen, which is a non-metal, has six electrons in its outer shell and needs two additional electrons to complete its valence shell and achieve stability. In this reaction, oxygen gains the two electrons that magnesium has lost, becoming a negatively charged ion (O²⁻).

This transfer of electrons leads to the formation of an ionic bond between magnesium and oxygen, resulting in the creation of magnesium oxide (MgO). The ionic bond is characterized by the electrostatic attraction between the positively charged magnesium ions and the negatively charged oxide ions, which is a fundamental aspect of how these two elements interact chemically.

In this context, the other options do not accurately depict the behavior of electrons during the formation of the bond; sharing of electrons does not occur here since this is not a covalent bond, and saying that electrons are not involved or combined to form a molecule does not represent the electron transfer that defines ionic bonding.