Sample interview questions: How do you calculate the entropy change of a system?
Sample answer:
To calculate the entropy change of a system, we need to consider the fundamental principles of thermodynamics and apply relevant equations. Entropy is a measure of the degree of disorder or randomness in a system, and its change can be determined using the following methods:
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Entropy Change for an Ideal Gas: For an ideal gas, the entropy change can be calculated using the equation ΔS = nCv ln(T2/T1), where ΔS is the entropy change, n is the number of moles of gas, Cv is the molar heat capacity at constant volume, T2 is the final temperature, and T1 is the initial temperature.
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Entropy Change for a Phase Transition: When a substance undergoes a phase transition (e.g., solid to liquid), the entropy change can be determined using the equation ΔS = q/T, where ΔS is the entropy change, q is the heat transferred during the phase transition, and T is the temperature.
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Entropy Change for a Reversible Process: In the case of a reversible process, the entropy change can be calculated using the equation ΔS = ∫(dQ/T), where ΔS is the entropy change, dQ is the infinitesimal amount of heat transferred, and T is t… Read full answer