What is the primary reason a real gas deviates from the ideal gas equation?
**Pressure-temperature relation** at constant volume Gay-Lussac law P ∝ T, for V constant, P₁/T₁ = P₂/T₂, if T doubles from 300 K to 600 K P doubles, e.g., P₁=1 atm at 300 K P₂=2 atm at 600 K, no work done, ΔU = n C_v ΔT = Q. Real gases deviate from the ideal gas equation ( P V = μ R T ) due to intermolecular forces, which are negligible in ideal gases but significant in real gases, especially at high pressures or low temperatures. Using first law ΔU = Q - W, W = ∫ P dV, isobaric W = P ΔV, isothermal
Ref: NCERT > Physics Book > Thermodynamics > Isochoric Processes and Pressure-Temperature