Which term describes substances that absorb water from the atmosphere and dissolve in the absorbed water to form a liquid?

• A. Efflorescent
• B. Deliquescent
• C. Hygroscopic
• D. Effervescent

Answer: (B)

Deliquescence is the process where a substance pulls moisture from the air and then dissolves in that absorbed water to form a liquid. The key idea is not just soaking up water, but actually dissolving into the absorbed water to create an aqueous solution. Hygrroscopic substances also attract and hold moisture, but they don’t necessarily dissolve and form a liquid. Efflorescent materials lose water to the air, not gain it, and effervescent materials release gas when dissolved. So the defining characteristic here is the absorption of water followed by dissolution into that water, making a liquid.