The substances NaF and CaO are isoelectronic (have the same number of valence electrons). (a) What are the charges on each of the cations in each compound?

Key Concepts

Isoelectronic Species

Isoelectronic species are atoms, ions, or molecules that have the same number of electrons. In the case of NaF and CaO, both compounds contain ions that achieve a stable electron configuration similar to noble gases, which is crucial for understanding their chemical behavior and bonding.

Cation Formation and Charge

Cations are positively charged ions formed when an atom loses one or more electrons. The charge of a cation is determined by the number of electrons lost; for example, sodium (Na) loses one electron to form Na⁺, while calcium (Ca) loses two electrons to form Ca²⁺. Understanding this helps in determining the charges of the cations in NaF and CaO.

Ionic Compounds and Charge Balance

Ionic compounds are formed from the electrostatic attraction between cations and anions, which must balance to create a neutral compound. In NaF, Na⁺ pairs with F⁻, while in CaO, Ca²⁺ pairs with O²⁻. Recognizing how these charges balance is essential for identifying the charges on the cations in each compound.