Which process involves the separation of an ionic substance into ions when immersed in water?

The process that involves the separation of an ionic substance into ions when it is immersed in water is known as disassociation. When an ionic compound is added to water, the polar water molecules interact with the positive and negative ions in the compound. This interaction leads to the breaking of the ionic bonds that hold the compound together, allowing the ions to separate and disperse throughout the solution.

Disassociation is critically important in various chemical and biological processes, particularly in understanding how salts dissolve in water and how ions move and interact in different environments, such as within marine ecosystems or during electrochemical reactions in marine corrosion.

In contrast, hydration refers to the process where water molecules surround and interact with the ions or molecules. While hydration occurs during disassociation, it is not the process of separation itself. Evaporation involves the transformation of liquid water into gas, and precipitation refers to the formation of a solid from a solution, often as a result of a reaction between two soluble substances.