Final answer:
Ammonium sulfate is an ionic compound classified as a salt, formed from the reaction between ammonia and sulfuric acid.
Step-by-step explanation:
Ammonium sulfate [(NH₄)₂SO₄] is an ionic compound that is classified as a salt. This compound is formed from the reaction of the weak base ammonia (NH₃) and sulfuric acid (H₂SO₄), a strong acid. When ammonium sulfate dissociates in water, the ammonium ion (NH₄+) acts as a Bronsted-Lowry acid by donating a proton to the water, forming hydronium (H₃O+) ions. Therefore, an aqueous solution of ammonium sulfate can be slightly acidic. However, the primary classification of ammonium sulfate is as a salt, being composed of both ammonium ions and sulfate ions (SO₄²⁻).