* Magnesium (Mg) has 2 valence electrons. It wants to lose these electrons to achieve a stable octet (8 electrons in its outer shell).
* Chlorine (Cl) has 7 valence electrons. It wants to gain one electron to achieve a stable octet.
To form an ionic bond:
* Magnesium will lose its two valence electrons, becoming a positively charged ion (Mg²⁺).
* Each chlorine atom will gain one electron, becoming negatively charged ions (Cl⁻).
Therefore, you need two chlorine atoms (2 x Cl⁻) to balance the charge of one magnesium ion (Mg²⁺).
The resulting compound is magnesium chloride (MgCl₂).
