Can a compound be both molecular and ionic?

📌 CONCEPT: A compound can exhibit both ionic and molecular properties depending on its structure and bonding. For instance, some compounds may consist of ions that are held together by strong electrostatic forces, while others may be made up of molecules with covalent bonds.

📐 RULE / FORMULA: According to the definition of an ionic compound, it is a chemical compound that is formed from the electrostatic attraction between oppositely charged ions. On the other hand, a molecular compound is formed by sharing electrons between atoms to form covalent bonds.

💡 WORKED EXAMPLE: Consider ammonium chloride (NH4Cl). Although it is composed of positively charged ammonium ions (NH4+) and negatively charged chloride ions (Cl-), it exists as a crystal lattice, which is characteristic of ionic compounds. However, the ammonium ion itself is a polyatomic ion formed by sharing electrons between nitrogen and hydrogen atoms. Therefore, NH4Cl is an example of a compound that exhibits both ionic and molecular properties.

⚠️ COMMON MISTAKE: Students often mistakenly assume that a compound can only be either ionic or molecular, and do not consider the possibility of a compound exhibiting both properties.