The GATE Grind

GATE Thermodynamics: Phase equilibria and vapour-liquid equilibrium – Previous Year Questions

6 GATE previous year questions on Phase equilibria and vapour-liquid equilibrium (Thermodynamics, Chemical Engineering) with answers and explanations, from every paper.

  1. GATE 2022 CH Q15 (1 mark, Multiple choice) – For a single component system at vapor-liquid equilibrium, the extensive variables A, V, S and N denote the Helmholtz free energy, volume, entropy,…
  2. GATE 2022 CH Q49 (2 marks, Numerical answer) – For a pure substance, the following data at saturated conditions are given: Psat (bar) T (K) --- --- 0.693 350 1.386 370 Assume that the vapor phase…
  3. GATE 2023 CH Q40 (2 marks, Multiple choice) – Water in a container at 290 K is exposed to air containing 3% CO 2 by volume. Air behaves like an ideal gas and is maintained at 100 kPa pressure. The…
  4. GATE 2024 CH Q18 (1 mark, Multiple choice) – Consider a vapour-liquid mixture of components A and B that obeys Raoult's law. The vapour pressure of A is half that of B. The vapour phase…
  5. GATE 2025 CH Q57 (2 marks, Numerical answer) – Components A and B form an azeotrope. The saturation vapour pressures of A and B at the boiling temperature of the azeotrope are 87 kPa and 72.7 kPa,…
  6. GATE 2026 CH Q36 (2 marks, Multiple choice) – K value is defined as the ratio of mole fraction of a component in the vapor phase to that in the liquid phase. The K values of propane and iso-butane…