The conjugate base of nitrous acid is the nitrite ion (NO2⁻).
Understanding the concept of conjugate acid-base pairs is central to acid-base chemistry. According to the Brønsted-Lowry theory, an acid is a proton (H⁺) donor, and a base is a proton acceptor. When an acid donates its proton, the species remaining is its conjugate base.
Nitrous Acid and Its Conjugate Base
Nitrous acid, with the chemical formula HNO2, is a weak acid. When nitrous acid acts as an acid, it donates a proton (H⁺). The chemical species that remains after this donation is the nitrite ion (NO2⁻). This nitrite ion is capable of accepting a proton to reform nitrous acid, thus functioning as a base in the reverse reaction.
The reaction demonstrating this relationship can be written as:
HNO2 (Nitrous Acid) ⇌ H⁺ + NO2⁻ (Nitrite Ion)
This equation shows that nitrous acid and the nitrite ion are interconvertible by the gain or loss of a single proton. The nitrite ion (NO2⁻) and nitrous acid (HNO2) present as a conjugated acid-base pair, a fundamental relationship critical to their chemical behavior in various solutions.
Key Characteristics of the Conjugate Pair
- Nitrous Acid (HNO2): Acts as the acid by donating a proton.
- Nitrite Ion (NO2⁻): Acts as the conjugate base by accepting a proton.
- The relationship is defined by the transfer of only one proton.
- The strength of an acid is inversely related to the strength of its conjugate base. Since nitrous acid is a weak acid, its conjugate base, the nitrite ion, is a relatively stronger base compared to the conjugate bases of strong acids.
Summary Table
To summarize the relationship between nitrous acid and its conjugate base:
| Component | Name | Chemical Formula | Role |
|---|---|---|---|
| Acid | Nitrous Acid | HNO2 | Proton Donor |
| Conjugate Base | Nitrite Ion | NO2⁻ | Proton Acceptor |
Further Information on Nitrite
The nitrite ion (NO2⁻) is a polyatomic ion that plays significant roles in various chemical and biological processes, including the nitrogen cycle. Its formation as the conjugate base of nitrous acid highlights its fundamental role in aqueous solutions where nitrous acid is present.
For more information on conjugate acid-base pairs, you can explore resources like Khan Academy's explanation of Brønsted-Lowry acid-base theory.
