Thermodynamics is not concerned about ________.

Options

A. energy changes involved in a chemical reaction
B. the extent to which a chemical reaction proceeds
C. the rate at which a reaction proceeds
D. the feasibility of a chemical reaction

Explanation

To solve the question "Thermodynamics is not concerned about ________", we need to analyze the options provided and determine which aspect is not related to thermodynamics.

### Step-by-Step Solution:

1. **Understand Thermodynamics**: Thermodynamics is a branch of chemistry that deals with the relationships between heat, work, temperature, and energy. It primarily focuses on energy changes, the feasibility of reactions, and the extent to which reactions can occur.

2. **Evaluate the Options**:
- **Energy changes involved in a chemical reaction**: Thermodynamics is indeed concerned with this aspect. It studies how energy is absorbed or released during chemical reactions.
- **The extent to which a chemical reaction proceeds**: Thermodynamics also addresses this, as it can predict whether a reaction can occur under certain conditions.
- **The rate at which a reaction proceeds**: This is where thermodynamics does not apply. The rate of a reaction is studied in chemical kinetics, not thermodynamics.
- **The feasibility of a chemical reaction**: Thermodynamics can determine if a reaction is feasible or spontaneous under given conditions.

3. **Identify the Correct Answer**: Since thermodynamics does not concern itself with the rate at which a reaction proceeds, the correct answer is **C: The rate at which a reaction proceeds**.

### Final Answer:
Thermodynamics is not concerned about **the rate at which a reaction proceeds**.

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