Exams › JEE Advanced › Chemistry
If the specific heat at constant pressure (Cp) is 10 cal at 1000 K, the initial temperature (T1) is 1000 K, the final temperature (T2) is 100 K, and the mass (m) is 32 g, what is the entropy change (ΔS) under constant pressure?
- ΔS = Cp ln(T2/T1)
- ΔS = 2.303 × Cp log(100/1000)
- ΔS = −23.03 cal/K
- None of these
Correct answer: ΔS = Cp ln(T2/T1)
Solution
Entropy change under constant pressure is given by the equation ΔS = Cp ln(T2/T1), where Cp is the specific heat at constant pressure, and T1 and T2 are the initial and final temperatures respectively
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