In a chemical reaction, the term ‘aq’ stands for aqueous. It indicates that a substance is dissolved in water.
When we see a substance labeled with ‘aq’, it means that the molecules of that substance are surrounded by water molecules, forming a solution. For example, when we write NaCl(aq), we are referring to sodium chloride dissolved in water.
This designation is crucial for understanding the behavior of chemicals in reactions, as it affects their solubility, reactivity, and the overall dynamics of the reaction. Aqueous solutions are often the medium in which many chemical reactions occur, especially in biological and environmental contexts.