Water has an unusually high…Group of answer choicesmolar massspecific heatheat of formationheat of combustion

To determine which property of water is unusually high among the provided options, let's analyze each choice:

1. Molar Mass: The molar mass of water (H₂O) is 18.015 g/mol, which is not particularly high compared to other substances.

2. Specific Heat: Water has a very high specific heat capacity of about 4.18 J/g°C. This means it can absorb a lot of heat before its temperature changes, which is a unique and critical property for climate and biological systems.

3. Heat of Formation: The heat of formation for water is negative, indicating that energy is released when water is formed from hydrogen and oxygen. It’s a standard value and does not particularly stand out.

4. Heat of Combustion: The heat of combustion is not a property of water itself, but rather of the substances that combust to produce water (like hydrogen).

Based on this analysis, the characteristic of water that is unusually high is specific heat. It is crucial for regulating temperatures in the environment and in biological systems.

Final Answer

Water has an unusually high specific heat.