Final answer:
Water has several unique properties, including existing in nature as a solid, liquid, and gas; having a density of ice that is less than liquid water; having a high heat capacity and heat of vaporization; and existing as a liquid at room temperature.
Step-by-step explanation:
Water has several properties that make it a unique substance among substances:
Exists in nature as a solid, liquid, and gas: Water can exist as ice (solid), liquid water, or water vapor (gas). This ability is due to the hydrogen bonding between water molecules.
The density of ice is less than liquid water: This property is why ice floats on water. When water freezes, the hydrogen bonds arrange in a way that increases the space between the molecules, making ice less dense.
Water has a high heat capacity: Water can absorb and store a large amount of heat energy without experiencing a large increase in temperature. This property helps regulate temperature on Earth and in living organisms.
Water has a high heat of vaporization: Water requires a significant amount of heat energy to change from a liquid to a gas. This property is important for cooling organisms through evaporation.
Water exists as a liquid at room temperature: Unlike most other substances, water is a liquid at normal room temperature. This property allows water to support life on Earth.