All Free Chemical Engineering MCQs with Answers
Every Chemical Engineering question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.
6,983 questions · page 1 of 350
- A. Law of Petit and Dulong
- B. Nernst heat theorem
- C. Kopp's rule
- D. Trouton's rule
Explanation: Kopp’s rule estimates a compound’s molar heat capacity by adding the approximate atomic heat capacities of its constituent elements.
Correct answer: Kopp's rule- A. Kinetic energy
- B. Intermolecular forces
- C. Potential energy
- D. Total energy
Explanation: At equilibrium and the same temperature, the average molecular kinetic energy is equal in both phases.
Correct answer: Kinetic energy- A. All A., B. & C.
- B. Melting
- C. Vaporisation
- D. Sublimation
Explanation: The Clausius-Clapeyron relation describes the slope of equilibrium curves for phase changes, including sublimation, melting and…
Correct answer: All A., B. & C.- A. Ostwald
- B. Cox
- C. Mollier's
- D. Enthalpy-concentration
Explanation: A Cox chart plots vapour pressure relationships and is closely related to the vapour-pressure correlation represented by the Antoine…
Correct answer: Cox5. If a solution of eutectic composition is cooled, _______________ reaching the eutectic temperature ?
- A. The solvent begins to freeze out even before
- B. It will not solidify even on
- C. It will undergo no change until
- D. None of these
Explanation: At the eutectic composition, neither component crystallizes preferentially before the eutectic temperature is reached.
Correct answer: It will undergo no change until- A. Mixing
- B. Adsorption
- C. Wetting
- D. Complete wetting
Explanation: Heat of complete wetting is the enthalpy change when a unit mass of solid is wetted until adding more liquid causes no further thermal…
Correct answer: Complete wetting- A. All A., B. & C.
- B. Concentration of solution
- C. Nature of solute
- D. Nature of solvent
Explanation: Heat of solution reflects interactions among solute, solvent and the resulting solution, so it changes with the nature of both substances…
Correct answer: All A., B. & C.- A. 0
- B. 10
- C. 7
- D. 14
Explanation: Equal hydrogen-ion and hydroxyl-ion concentrations indicate a neutral aqueous solution.
Correct answer: 7- A. Pressure
- B. Volume
- C. Molecularity
- D. Temperature
Explanation: Kirchhoff’s equation relates the change in heat of reaction with temperature through the difference between the heat capacities of…
Correct answer: Temperature- A. Kirchoff's
- B. Maxwell's
- C. Antoine
- D. Kistyakowsky
Explanation: Kirchhoff’s equation gives how the heat of reaction changes with temperature by accounting for the heat-capacity change between products…
Correct answer: Kirchoff's- A. Increases its freezing point
- B. Both B. and C.
- C. Decreases its freezing point
- D. Increases its boiling point
Explanation: A nonvolatile solute lowers the solvent’s vapour pressure, so a higher temperature is needed to boil it and a lower temperature at which…
Correct answer: Both B. and C.- A. PvB
- B. xB.Patm
- C. (Patm - Pvw)xB
- D. xB.PvB
Explanation: For an ideal liquid solution, Raoult’s law gives the benzene partial pressure as the liquid mole fraction multiplied by benzene’s…
Correct answer: xB.PvB13. The quantity of heat required to evaporate 1 kg of a saturated liquid is called __________________?
- A. Latent heat
- B. 1 Kcal
- C. Sensible heat
- D. Specific heat
Explanation: Latent heat is the heat required for a phase change at essentially constant temperature, such as converting 1 kg of saturated liquid into…
Correct answer: Latent heat- A. Do not lose energy on collision
- B. Do not exert attractive force on each other
- C. Are above the inversion temperature
- D. Do work equal to loss in kinetic energy
Explanation: In the free expansion of an ideal gas, there are no intermolecular attractive forces, so internal energy and temperature do not change.
Correct answer: Do not exert attractive force on each other- A. Osmotic pressure
- B. Depression of freezing point
- C. None of these
- D. Lowering of vapor pressure
Explanation: Osmotic pressure, freezing-point depression, and vapour-pressure lowering all depend on the number of solute particles rather than their…
Correct answer: None of these- A. 1
- B. 2
- C. 4
- D. 8
Explanation: The mole fraction of nitrogen is 2/(6+2) = 0.25. Dalton’s law then gives its partial pressure as 0.25 × 4 = 1 kgf/cm².
Correct answer: 1- A. Equilibrium constant
- B. Changes in heat of reaction
- C. Reaction rate
- D. None of these
Explanation: Hess’s law states that the heat or enthalpy change of a reaction is independent of the route and depends only on the initial and final…
Correct answer: Changes in heat of reaction- A. St
- B. 1/St
- C. Sv
- D. 1/Sv
Explanation: For an ideal solution, Raoult’s law gives the solvent partial vapour pressure as pᵥ = xᵥPᵥ°, so vapour pressure is proportional to the…
Correct answer: Sv- A. 380
- B. 630
- C. 760
- D. 880
Explanation: At constant volume for an ideal gas, temperature follows absolute pressure, so T2 = 300(330/300) = 330 K and ΔT = 30 K.
Correct answer: 630- A. 1
- B. 2.42
- C. 4.97
- D. None of these
Explanation: Using 1 kcal = 3.968 BTU, 1 kg = 2.205 lb, and 1°C = 1.8°F gives 3.968/(2.205 × 1.8) = 1 BTU/lb·°F.
Correct answer: 1