Among the following, the set of parameters that represents path functions is
(A) q + w (B) q (C ) w (D) H - TS

Options

A. (A), (B) and (C)
B. (B) and (C)
C. (A) and (D)
D. (B), (C) and (D).

Explanation

To solve the question of identifying the set of parameters that represents path functions among the given options, we will follow these steps:

### Step 1: Understand the Definitions
1. **State Functions**: These are properties that depend only on the state of the system, not on how it got there. Examples include internal energy (U), enthalpy (H), and entropy (S).
2. **Path Functions**: These depend on the specific path taken to reach a particular state. Examples include heat (q) and work (w).

**Hint**: Remember that state functions are determined by the initial and final states, while path functions depend on the process taken.

### Step 2: Analyze Each Option
- **Option A: q + w**
- This represents the change in internal energy (ΔU), which is a state function. Therefore, this option is not a path function.

- **Option B: q**
- Heat (q) is a path function because it depends on the specific process taken to transfer energy.

- **Option C: w**
- Work (w) is also a path function for the same reason; it depends on the path taken during the process.

- **Option D: H - TS**
- This expression is related to Gibbs free energy (G), which is a state function. Therefore, this option is not a path function.

**Hint**: Evaluate each option based on whether it depends on the path taken or just the initial and final states.

### Step 3: Identify the Correct Options
From the analysis:
- **Path Functions**:
- Option B: q (Heat)
- Option C: w (Work)

- **Not Path Functions**:
- Option A: q + w (State function)
- Option D: H - TS (State function)

### Conclusion
The set of parameters that represents path functions is **(B) q and (C) w**.

### Final Answer
The correct answer is: **(B) q and (C) w**.