- Ionic bonds form via the electrostatic attraction between a cation (+) and an anion (-).
- Sr is a metal that forms a cation, Ne is inert, and \(NH_4^+\) is a cation; thus, none of these form ionic bonds with other cations.
- \(PO_4^{3-}\) is a polyatomic anion that carries a negative charge, making it the only option capable of forming an ionic bond with a cation.
- The final answer is \(\boxed{PO_4^{3-}}\).
Explanation
- Understanding Ionic Bonds
An ionic bond is defined as the electrostatic attraction between oppositely charged ions: a positively charged ion, known as a cation, and a negatively charged ion, known as an anion. Therefore, to identify which substance can easily form an ionic bond with a cation, we must look for a species that acts as an anion.
- Evaluating the Options
Let us analyze each of the provided options:
- Sr (Strontium): Strontium is a Group 2 metal. In its ionic form, it loses two electrons to become a cation (\(Sr^{2+}\)). Since it is a cation, it will not form an ionic bond with another cation due to electrostatic repulsion.
- Ne (Neon): Neon is a noble gas with a complete outer shell of electrons. It is chemically inert and does not readily gain or lose electrons to form ions.
- \(NH_4^+\) (Ammonium): This is a polyatomic ion with a positive charge. Because it is a cation, it will not form an ionic bond with another cation.
- \(PO_4^{3-}\) (Phosphate): This is a polyatomic ion with a negative charge. As an anion, it carries the necessary negative charge to experience electrostatic attraction toward a positive cation, allowing for the formation of an ionic bond.
- Identifying the Correct Choice
Based on our analysis, the only species among the options that acts as an anion is \(PO_4^{3-}\). Consequently, it is the only one capable of forming an ionic bond with a cation. Therefore, the correct option is \(PO_4^{3-}\).
Examples
The formation of ionic bonds is essential for the structure of many substances we use every day. For example, when you use a phosphate-based cleaner or fertilizer, those compounds often rely on the stable ionic bonds formed between the phosphate anion (\(PO_4^{3-}\)) and various metal cations like calcium (\(Ca^{2+}\)) or sodium (\(Na^+\)). Understanding these interactions helps chemists design effective materials for everything from agriculture to household maintenance.