Using only the elements P, Br, and Mg, give formulas for the following.(b) A molecular compound with polar covalent bonds that obeys the octet rule and has no formal charges

Verified step by step guidance

1. insert step 1> Identify the elements involved: Phosphorus (P), Bromine (Br), and Magnesium (Mg).
2. insert step 2> Recognize that a molecular compound typically involves nonmetals, so focus on P and Br, as Mg is a metal.
3. insert step 3> Consider the valence electrons: P has 5 valence electrons, and Br has 7 valence electrons.
4. insert step 4> Aim to form a compound where each atom achieves an octet. Phosphorus can form three bonds to achieve an octet, while each Bromine can form one bond.
5. insert step 5> Construct a compound where Phosphorus is central and forms three single bonds with three Bromine atoms, resulting in the formula PBr3.

Key Concepts

Polar Covalent Bonds

Polar covalent bonds occur when two atoms with different electronegativities share electrons unequally, resulting in a molecule with a partial positive charge on one end and a partial negative charge on the other. This uneven distribution of charge creates a dipole moment, which is essential for determining the polarity of the compound.

Octet Rule

The octet rule states that atoms tend to form bonds in such a way that they each have eight electrons in their valence shell, achieving a stable electron configuration similar to that of noble gases. This rule is a guiding principle in predicting the formation of molecular compounds, particularly in covalent bonding.

Formal Charges

Formal charge is a theoretical charge assigned to an atom in a molecule, calculated based on the number of valence electrons, the number of non-bonding electrons, and half the number of bonding electrons. A molecule with no formal charges is often more stable, as it indicates that the electrons are distributed in a way that minimizes charge separation.