which of the following statements are correct regarding to galvanic cell?

Options

A. A reaction is spontaneous from right to left if `E_(cell)gt0`
B. A reaction occurs from right to left if `E_(cell)lt0`
C. If the system is at equilibrium no net reaction occurs
D. `E_(cell)` is temperature-independent

Answer

To determine which statements are correct regarding a galvanic cell, we can analyze each statement based on our understanding of electrochemistry and the principles governing galvanic cells. Here’s a step-by-step solution:

### Step 1: Understand the Components of a Galvanic Cell
A galvanic cell consists of two electrodes: the anode and the cathode.
- **Anode**: The site of oxidation (loss of electrons).
- **Cathode**: The site of reduction (gain of electrons).

### Step 2: Analyze Each Statement
Now, let's evaluate the statements provided in the question.

#### Statement A: "A reaction is spontaneous from right to left."
- In a galvanic cell, a spontaneous reaction occurs when the cell potential (E_cell) is greater than 0. If the reaction is said to be from right to left, it implies that E_cell would be less than 0, indicating a non-spontaneous reaction. Thus, this statement is **false**.

#### Statement B: "A reaction occurs from right to left if E_cell is less than 0."
- This statement is correct. If E_cell is less than 0, it indicates that the reaction is non-spontaneous in the forward direction, meaning it would proceed in the reverse direction (right to left). Therefore, this statement is **true**.

#### Statement C: "If the system is at equilibrium, no net reaction occurs."
- At equilibrium, the cell potential (E_cell) is equal to 0, which means there is no driving force for the reaction to proceed in either direction. Hence, there is no net change occurring in the system. This statement is **true**.

### Step 3: Conclusion
Based on the analysis:
- Statement A is **false**.
- Statement B is **true**.
- Statement C is **true**.

Thus, the correct statements regarding the galvanic cell are **B and C**.

### Summary of Correct Answers:
- **B**: True
- **C**: True