In solutions, what property determines whether a substance dissolves in water?

• A. Viscosity
• B. Density
• C. Solubility
• D. Boiling point

Answer: (C)

Solubility is the property that describes how well a substance can dissolve in water. It depends on how the particles of the substance interact with water molecules—when these interactions are favorable (such as ions separating and becoming surrounded by water, or polar molecules forming hydrogen bonds with water), the substance dissolves to form a solution. Viscosity, density, and boiling point describe other characteristics of a substance and do not determine whether it will dissolve in water.