For a system undergoing a first-order phase transition at a temperature \(T_c\), which one of the following graphs best describes the variation of entropy (S) as a function of temperature (T)?
For a system undergoing a first-order phase transition at a temperature \(T_c\), which one of the following graphs best describes the variation of entropy (S) as a function of temperature (T)?
Show Hint
- (A)
- (B)
- (C)
- (D)
The Correct Option is D
Solution and Explanation
Step 1: Understanding the concept.
In a first-order phase transition, the entropy changes discontinuously at the transition temperature \(T_c\), corresponding to the latent heat of the transformation.
Step 2: Interpreting the graphs.
Among the given graphs, only Graph (D) shows a sudden jump in entropy at \(T_c\), indicating a discontinuous change.
Step 3: Conclusion.
Therefore, Graph (D) represents the correct variation of entropy during a first-order phase transition.
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