The enthalpy is maximum for

Options

A. 10 gram of water
B. 10 gram of ice
C. 10 gram of steam
D. same for all

Answer

To determine the state of water for which the enthalpy is maximum, we need to analyze the different states of water: solid (ice), liquid (water), and gas (water vapor).

### Step-by-Step Solution:

1. **Understanding Enthalpy**:
- Enthalpy (H) is a thermodynamic property that reflects the heat content of a system. It is defined as H = U + PV, where U is the internal energy, P is the pressure, and V is the volume.

2. **Different States of Water**:
- Water exists in three states: solid (ice), liquid (water), and gas (water vapor). Each state has a different enthalpy due to the differences in molecular arrangement and energy.

3. **Comparing Enthalpy of Different States**:
- In general, the enthalpy increases as we move from solid to liquid to gas. This is because:
- In the solid state (ice), molecules are tightly packed and have lower energy.
- In the liquid state (water), molecules are less tightly packed and have more energy.
- In the gaseous state (water vapor), molecules are far apart and have the highest energy.

4. **Conclusion**:
- Therefore, the enthalpy is maximum for water in its gaseous state (water vapor).

### Final Answer:
The enthalpy is maximum for water in the gaseous state (water vapor).

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