Question

state first law of thermodynamics and obtain an expression for isothermal process​

Answer 1

It is also worth noting that for ideal gases, if the temperature is held constant, the internal energy of the system also is constant, and so ΔU = 0. Since the First Law of Thermodynamics states that ΔU = Q + W (IUPAC convention), it follows that Q = −W for the isothermal compression or expansion of ideal gases.

Answer 2

Answer:

∆U=q+w

for isothermal process ∆U=0

so, q= -w or Q= -W

Where,

Q=q=heat change

∆U= Internal energy change

W= Work done