The term for substances that readily absorb moisture from the air is which of the following?

• A. Immiscible
• B. Hygroscopic
• C. Deliquescent
• D. Eutectic

Answer: (B)

Hygroscopic behavior describes substances that readily absorb moisture from the air. They attract water vapor from the surrounding atmosphere, which is why humid conditions cause such materials to gain moisture or clump. Deliquescent is a stronger form where enough moisture is absorbed to dissolve the substance into a liquid, which is a subset of hygroscopic behavior. Immiscible refers to liquids that don’t mix, and eutectic is about a melting-point relationship in a mixture, not moisture uptake. So the term you’re looking for is hygroscopic.