To obtain integrated form of Clausius-Clapeyron equation, ln (P2/P1) = (ΔHV/R) (1/T1 - 1/T2) from the exact Clapeyron equation, it is assumed that the

Volume of the liquid phase is negligible compared to that of vapour phase

Vapour phase behaves as an ideal gas

Heat of vaporisation is independent of temperature

All (A), (B) & (C)

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