Which compound is also known as silver nitrate?

Silver nitrate is a compound that consists of silver cations (Ag⁺) and nitrate anions (NO₃⁻). Its chemical formula is represented as AgNO₃, which directly corresponds to the correct choice.

The name "silver nitrate" highlights that the compound contains silver along with the nitrate ion. The nitrate ion is a polyatomic ion made up of one nitrogen atom covalently bonded to three oxygen atoms. This combination of silver and nitrate gives silver nitrate its characteristic properties and usage in various applications, including photography and as a chemical reagent.

The other compounds listed do not match the formula for silver nitrate. For example, AgCl is silver chloride, Ag₂O is silver oxide, and AgSO₄ is silver sulfate. Each of these has a different combination of silver and other elements, which results in distinct chemical properties and nomenclature that do not align with silver nitrate. Thus, the identification of AgNO₃ as silver nitrate is both accurate and essential for understanding chemical nomenclature.