Which compound is not ionic based on electronegativity?

Which compound is not ionic based on electronegativity?

• A. C3H8
• B. BaF2
• C. MgCl2
• D. NaI

Answer: (A)

Bonding type is determined by how strongly atoms attract electrons to themselves. When the difference in electronegativity between two bonded atoms is large, electrons tend to be transferred from one atom to the other, creating ions that attract each other in a crystal lattice—an ionic compound. When the difference is small, electrons are shared rather than transferred, forming covalent bonds and discrete molecules. Propane (C3H8) is made entirely of carbon and hydrogen. Their electronegativities are close enough that the bonds are formed by sharing electrons rather than transferring them, so propane is a covalent molecule, not ionic. The other compounds involve a metal and a nonmetal, which creates a strong tendency for electron transfer and formation of ions. Those ions arrange into an ionic lattice, characteristic of ionic compounds.

Bonding type is determined by how strongly atoms attract electrons to themselves. When the difference in electronegativity between two bonded atoms is large, electrons tend to be transferred from one atom to the other, creating ions that attract each other in a crystal lattice—an ionic compound. When the difference is small, electrons are shared rather than transferred, forming covalent bonds and discrete molecules.

Propane (C3H8) is made entirely of carbon and hydrogen. Their electronegativities are close enough that the bonds are formed by sharing electrons rather than transferring them, so propane is a covalent molecule, not ionic.

The other compounds involve a metal and a nonmetal, which creates a strong tendency for electron transfer and formation of ions. Those ions arrange into an ionic lattice, characteristic of ionic compounds.