Final answer:
The conjugate base of hydrazoic acid (HN₃) is the azide ion (N₃-). Since hydrazoic acid is a weak acid, its conjugate base is stronger and capable of accepting protons.
Step-by-step explanation:
The conjugate base of a weak acid tends to be a stronger base. In the case of hydrazoic acid (HN₃), the conjugate base is formed by the loss of a hydrogen ion (H+), resulting in the azide ion (N₃-). To understand this process, let's consider the dissociation reaction of hydrazoic acid:
HN₃ (aq) → H+ (aq) + N₃- (aq)
Through this reaction, the hydrazoic acid acts as a Brønsted-Lowry acid by donating a proton, and the resulting azide ion is its conjugate base. According to the Brønsted-Lowry Acid-Base Theory, strong acids have weak conjugate bases, and weak acids have stronger conjugate bases. Since hydrazoic acid is a weak acid, its conjugate base, the azide ion, is stronger and can effectively compete with water for possession of protons.
The strength of the conjugate base is significant because it determines the degree of ionization of the acid in water. For hydrazoic acid, the equilibrium favors the reactants, which means there is less ionization compared to strong acids. This characteristic provides the azide ion with the capacity to accept protons, which defines it as a relatively stronger base.