Which of the following processes involves the greatest release of energy from water molecules?

• A. Condensation of water vapor to liquid water
• B. Freezing of liquid water to ice
• C. Deposition of water vapor to ice
• D. Cooling of liquid water from 25°C to 0°C

Answer: (A)

Verified step by step guidance

1. Understand that energy release in these processes is related to phase changes or temperature changes involving water molecules. Phase changes like condensation, freezing, and deposition involve latent heat, while cooling involves sensible heat.
2. Recall that condensation (gas to liquid), freezing (liquid to solid), and deposition (gas to solid) are exothermic processes where water molecules release energy as they form stronger intermolecular bonds.
3. Recognize that deposition (gas to solid) combines condensation and freezing, so it generally releases more energy than either condensation or freezing alone because it skips the liquid phase.
4. Compare the latent heats involved: latent heat of vaporization (condensation), latent heat of fusion (freezing), and the sum of both for deposition. Cooling from 25°C to 0°C releases energy only through temperature decrease, not phase change, so it releases less energy.
5. Conclude that the process involving the greatest release of energy is the one with the largest latent heat change, which is deposition (gas to solid), as it releases both the heat of vaporization and fusion combined.