How to Solve Thermodynamics Problems when an Ideal Gas Undergoes Reversible Isothermal Expansion – Part 1

The first law of thermodynamics states that, when energy passes into or out of a system (as work, heat, or matter), the system's internal energy changes in accordance with the law of conservation of energy.


An isothermal process means no change in temperature.

Question:

Calculate the work done by the reversible isothermal expansion of an ideal gas from a pressure of P1 = 1 bar and a volume of V1 = 2 dm3 to a final pressure of P2 = 0.25 bar. 1 bar dm3 = 100 J.

Solution:



Click to enlarge the image

w = Work done, n = Number of moles, R = Gas constant, T = Absolute temperature, V = Volume, P = Pressure

Thrilled by thermodymanics❓ Let Chemaficionado know at mychemistryhomework@gmail.com❗

References:
(1)    Wikipedia Contributors. Laws of thermodynamics. Wikipedia. https://en.wikipedia.org/wiki/Laws_of_thermodynamics.

(2)    Ncert. Chemistry : Textbook for Class XI - Part.I; National Council Of Educational Research And Training: New Delhi.

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