Question

note: to answer some of the questions, it may help to reference a periodic table
how can the octet rule be used to explain why one magnesium (mg) atom would bond with one oxygen (o) atom?
oxygen has six valence electrons; it needs to gain two electrons to reach the octet rule with a full second energy orbital. magnesium has two valance electrons; it would prefer to lose both valence electrons to reach the octet rule of a full second energy orbital. therefore, one magnesium atom can satisfy the needs of the oxygen atom to form an ionic bond.
magnesium has six valence electrons; it needs to gain two electrons to reach the octet rule with a full second energy orbital. oxygen has two valance electrons; it would prefer to lose both valence electrons to reach the octet rule of a full second energy orbital. therefore, one magnesium atom can satisfy the needs of the oxygen atom to form an ionic bond.
oxygen has six valence electrons; it needs to lose these electrons to reach the octet rule with a full second energy orbital. magnesium has two valance electrons; it would prefer to gain six valence electrons to reach the octet rule of a full second energy orbital. therefore, one magnesium atom can satisfy the needs of the oxygen atom to form an ionic bond.
oxygen has one valence electron; it needs to gain two electrons to reach the octet rule with a full first energy orbital. magnesium has one valance electron;

Explanation:

• Magnesium (Mg) is in Group 2 of the periodic table. Atoms in Group 2 have 2 valence electrons. To achieve a stable octet (full outer shell), Mg prefers to lose these 2 valence electrons.
• Oxygen (O) is in Group 16 of the periodic table. Atoms in Group 16 have 6 valence electrons. To achieve a stable octet, O needs to gain 2 electrons.
• When one Mg atom loses 2 electrons (becoming \(Mg^{2+}\)) and one O atom gains 2 electrons (becoming \(O^{2 -}\)), they form an ionic bond (due to the electrostatic attraction between the positive and negative ions) and both achieve a stable octet configuration.

Answer:

The first option: Oxygen has six valence electrons; it needs to gain two electrons to reach the octet rule with a full second energy orbital. Magnesium has two valence electrons; it would prefer to lose both valence electrons to reach the octet rule of a full second energy orbital. Therefore, one magnesium atom can satisfy the needs of the oxygen atom to form an ionic bond.