How Do We Calculate Entropy Change for an Ideal Gas?

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To calculate the entropy change for an ideal gas involving n moles, the equation used is ΔS = nCvln(T2/T1) + nRln(V2/V1). The first term represents the change in entropy due to temperature variation, while the second term accounts for volume change, potentially in isothermal conditions. However, the original question does not specify the type of process, leading to confusion about the derivation of the answer. Clarification on the process type is essential for accurately applying the entropy change formula. Understanding the context of the process is crucial for correctly interpreting the entropy change calculation.
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Homework Statement


The question says:
In a process involving n moles of an ideal gas , what is the entropy change of the system ?

Homework Equations


ΔS=qrev/T=(ΔU-w)/T
(I have used the chemistry's equation of 1st law of thermodynamics which has the -ve sign)

The Attempt at a Solution


The answer given is that:
nCvln(T2/T1)+nRln(V2/V1).
I don't know how they are giving this answer. The second term seems to be originated from work done in isothermal conditions . But its not given that the process is an isothermal one. And the first term ...huh..I don't know where it came from. So what is the origin of this answer?
 
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mooncrater said:
In a process

What process?
 
Borek said:
What process?
There is nothing else given in the question.
 

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