Which of the following is a path function

Options

A. Internal energy
B. Enthalpy
C. Work
D. Entropy

Explanation

To determine which of the following is a path function, we need to understand the concept of path functions and state functions in thermodynamics.

### Step-by-Step Solution:

1. **Define Path Function**: A path function is a property that depends on the specific path taken during a thermodynamic process. Its value can vary based on how the process is carried out.

2. **Identify Examples of Path Functions**: Common examples of path functions include work and heat. These quantities depend on the process taken to go from one state to another.

3. **Contrast with State Functions**: State functions, on the other hand, are properties that depend only on the initial and final states of a system, regardless of the path taken. Examples include internal energy, enthalpy, and potential energy.

4. **Analyze the Options**: In the given options, we need to identify which one is a path function.
- If we consider work, it is dependent on the path taken (e.g., lifting an object by stairs versus using a lift).
- Other options (like internal energy, enthalpy, etc.) are state functions as their values are determined solely by the initial and final states.

5. **Conclusion**: Based on the analysis, the correct answer is that work is a path function.

### Final Answer:
The path function among the given options is **work**.

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