Liquids that dissolve freely in one another in any proportion are known as what?

• A. Miscible
• B. Solubility
• C. Hydration
• D. Anhydrous

Answer: (A)

This question tests the idea of miscibility: liquids that dissolve freely in any proportion form a single homogeneous phase. When two liquids are miscible, you can mix them in any amounts and you won’t see layering; they blend completely, as with ethanol and water. This contrasts with other terms: solubility describes how much of a substance can dissolve in a solvent under set conditions (not about two liquids forming one phase in all proportions), hydration is the process of ions or molecules becoming surrounded by water, and anhydrous means without water. Some liquids are immiscible, like oil and water, which separate into distinct layers. The essence here is that miscible liquids mix to form one liquid regardless of the ratio.