1. The problem statement, all variables and given/known data Two moles of an ideal gas undergo a reversible isothermal expansion from 3.37×10−2m3 to 4.29×10−2m3 at a temperature of 29.6 ∘C. What is the change in entropy ΔS of the gas? 2. Relevant equations pV=nRT 3. The attempt at a solution W=∫V2V1pdV, I don't know how to use this integral. And is it necessary to use this integral here? It seems like it is making the calculation more complicated than it should be. I have no other idea on how to approach this question. Please give me some hints!