What characterizes an ionic compound?

An ionic compound is characterized by being composed of positively and negatively charged ions. This occurs when atoms transfer electrons from one to another, resulting in the formation of ions: cations (positively charged) and anions (negatively charged). This transfer of electrons creates a strong electrostatic force of attraction between the oppositely charged ions, which leads to the formation of a stable ionic lattice structure.

The other options do not accurately describe ionic compounds. For instance, ionic compounds do not consist of neutral covalent bonds, nor are they formed through the sharing of electrons, which is characteristic of covalent compounds. Additionally, ionic compounds are not limited to only nonmetal elements; they often involve metals and nonmetals, such as sodium chloride (NaCl), which features sodium (a metal) and chloride (a nonmetal). Thus, the defining feature of ionic compounds is indeed their composition of charged ions that results from electron transfer.