Magnesium has two valence electrons and oxygen has six valence electrons. The electronegativity difference between the two elements is 2.13.
How can the octet rule be used to explain the bonding between magnesium and oxygen?
A. Oxygen needs access to two electrons to satisfy the octet rule. Magnesium prefers to lose two valence electrons to satisfy the octet rule. Oxygen can remove two electrons from magnesium, forming ions; leading to an ionic bond.
B. Oxygen needs to lose six electrons to satisfy the octet rule. Magnesium needs access to six valence electrons to satisfy the octet rule. Magnesium can remove six electrons from oxygen, forming ions and leading to an ionic bond.
C. Oxygen needs access to two electrons to satisfy the octet rule. Magnesium prefers to lose two valence electrons to satisfy the octet rule. Magnesium and oxygen can share two electrons, leading to a covalent bond.
D. Oxygen needs to lose six electrons to satisfy the octet rule. Magnesium needs access to six valence electrons to satisfy the octet rule. Magnesium and oxygen can share six electrons, leading to a covalent bond.
To determine the correct answer based on the octet rule, we need to understand the rule itself. The octet rule states that elements tend to gain, lose, or share electrons in order to achieve a full outer electron shell with eight electrons. This typically applies to elements in Periods 2 and 3 of the periodic table.
Option A suggests that oxygen can remove two electrons from magnesium to form ions, leading to an ionic bond. However, this does not follow the octet rule since oxygen would still have six valence electrons instead of eight.
Option B suggests that oxygen can lose six electrons to satisfy the octet rule, which is incorrect. Oxygen is highly electronegative and tends to gain electrons instead of losing them.
Option C suggests that magnesium and oxygen can share two electrons, leading to a covalent bond. This would satisfy the octet rule for both elements as oxygen would have eight electrons by sharing two electrons and magnesium would also have eight electrons by losing two electrons.
Option D suggests that magnesium and oxygen can share six electrons, leading to a covalent bond. This would not satisfy the octet rule for either element as oxygen would still have only six valence electrons and magnesium would have additional electrons.
Based on the octet rule, the correct answer is C. Oxygen needs access to two electrons to satisfy the octet rule. Magnesium prefers to lose two valence electrons to satisfy the octet rule. Magnesium and oxygen can share two electrons, leading to a covalent bond.
And you think what?
First, can you identify the kind of bond: i.e., ionic or covalent?
Do you know how many electrons Mg wants to gain or lose?
Do you know how many electrons O wants to gain or lose?
Knowing those last three questions will tell you what the answer should be.