Description : In case of absorption & stripping, the interface of the liquid & gas phases are present in equilibrium, when the diffusional resistance of __________ is zero. (A) Interface (B) Gas phase (C) Liquid phase (D) All 'a', 'b' & 'c'
Last Answer : (A) Interface
Description : Experiments were conducted to determine the flux of a species A in a stagnant medium across a gas-liquid interface. The overall mass transfer coefficient based on the liquid side for dilute systems for the above was estimated to be 4 ... -4 (C) 5.6 10 -3 (D) 8.5 10 -3
Last Answer : (B) 8.5 × 10 -4
Description : If a two phase system is in physical equilibrium; then it means that, the (A) Escaping tendency of each component from the liquid phase to the vapor phase is exactly equal to that from vapor phase to liquid phase ... liquid phase is equal to that throughout the vapor phase (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : When liquid and vapour phase of multi-component system are in equilibrium (at a given temperature and pressure), then chemical potential of each component is (A) Same in both the phases (B) Zero in both the phases (C) More in vapour phase (D) More in liquid phase
Last Answer : (A) Same in both the phases
Description : If the vapour pressure at two temperatures of a solid phase in equilibrium with its liquid phase are known, then the latent heat of fusion can be calculated by the (A) Maxwell's equation (B) Clausius-Clapeyron Equation (C) Van Laar equation (D) Nernst Heat Theorem
Last Answer : B) Clausius-Clapeyron Equation
Description : When liquid and vapour phases of one component system are in equilibrium (at a given temperature and pressure), the molar free energy is (A) More in vapour phase (B) More in liquid phase (C) Same in both the phases (D) Replaced by chemical potential which is more in vapour phase
Last Answer : (C) Same in both the phases
Description : The reaction A (l) → R(g) is allowed to reach equilibrium conditions in an autoclave. At equilibrium, there are two phases, one a pure liquid phase of A and the other a vapor phase of A, R and S. Initially A alone is present. The numbers of degrees of freedom are: (A) 1 (B) 2 (C) 3 (D) 0
Last Answer : (B) 2
Description : A reasonably general expression for vapour-liquid phase equilibrium at low to moderate pressure is φi yi P = Yi xifi° where, Φ is a vapor fugacity component, Yiis the liquid activity co- ... and liquid composition xi only (D) Temperature, pressure, liquid composition xi and vapour composition yi
Last Answer : (C) Temperature, pressure and liquid composition xi only
Description : What is the unique state at which solid, liquid and gaseous phase can go co-exist in equilibrium? a. Triple point b. Critical point c. Boiling point d. Pour point
Last Answer : Triple point
Description : The pressure of the vapor phase of a substance that is in equilibrium with the liquid or solid phase. a. Phase Pressure b. Equilibrium Vapor Pressure c. Specific Pressure d. Equilibrium Phase Pressure
Last Answer : Equilibrium Vapor Pressure
Description : Consider the following gas - phase reaction : `2A(g)+B(g)rArrC(g)+D(g)` An equilibrium mixture of reactants and products is subjected to the following
Last Answer : Consider the following gas - phase reaction : `2A(g)+B(g)rArrC(g)+D(g)` An equilibrium mixture of reactants and ... II, III C. II, III, IV D. I, III
Description : In a packed tower, the value of HETP equals HTUOG, when the equilibrium and the operating lines are (where, HETP = height equivalent to a theoretical plate HTUOG = overall gas phase height of a transfer unit). (A) Straight (B) Parallel (C) Both (A) & (B) (D) Neither (A) nor (B
Last Answer : (C) Both (A) & (B)
Description : For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant (A) Is independent of pressure (B) Increases with pressure (C) Decreases with pressure (D) Increases /decreases with pressure depending on the stoichiometric coefficients of the reaction
Last Answer : (B) Increases with pressure
Description : Pick out the wrong statement. (A) The conversion for a gas phase reaction increases with decrease in pressure, if there is an increase in volume accompanying the reaction (B) With ... phase reaction increases with increase in pressure, if there is a decrease in volume accompanying the reaction
Last Answer : (B) With increase in temperature, the equilibrium constant increases for an exothermic reaction
Description : The equilibrium constant for the gas phase reactio A + B = C + D is 10-3. The rate of the forward reaction is 10-11 cubic centimeters per molecule per second. What is the rate constant of ... second y) 10-10 cubic centimeters per molecule per second z) 10-14 cubic centimeters per molecule per second
Last Answer : ANSWER: Z -- 10-14 CUBIC CENTIMETERS PER MOLECULE PER SECOND
Description : In saturated gas, the (A) Vapour is in equilibrium with the liquid at the gas temperature (B) Vapour is in equilibrium with the liquid at the room temperature (C) Partial pressure of vapour equals the vapour pressure of the liquid at room temperature (D) None of these
Last Answer : (A) Vapour is in equilibrium with the liquid at the gas temperature
Description : . The absorption factor is defined as (where, L = liquid flow rate, G = gas flow rate and, m = slope of the equilibrium line). (A) L/mG (B) G/mL (C) mL/G (D) LG/m
Last Answer : (A) L/mG
Description : Pick out the wrong statement. (A) When the concentration difference for the mass transfer becomes zero at the bottom of the gas absorption tower, then the upper end of the operating line touches the ... fixed gas flow rate, the slope of the operating line decreases, in case of gas absorption process
Last Answer : (C) The operating line lies above the equilibrium curve in case of a gas desorber
Description : The individual mass transfer co-efficients (moles/m2s) for absorption of a solute from a gas mixture into a liquid solvent are, KL = 4.5 and KG = 1.5. The slope of the equilibrium line is 3. Which of ... A) Liquid side (B) Gas side (C) Interfacial (D) Both liquid and gas side
Last Answer : (B) Gas side
Description : Pick out the wrong statement (A) Co-current absorbers are usually used, when the gas to be dissolved in the liquid is a pure substance (B) In case of gas absorption, HETP is ... reaction (D) In actual practice, absorption is an endothermic process, while stripping is an exothermic process
Last Answer : (D) In actual practice, absorption is an endothermic process, while stripping is an exothermic process
Description : During ecological succession (a) the numbers and types of animals remain constant (b) the changes lead to a community that is in near equilibrium with the environment and is called pioneer community ( ... area (d) the establishment of a new biotic community is very fast in its primary phase.
Last Answer : (c) the gradual and predictable change in species composition occurs in a given area
Description : Pick out the wrong statement. (A) Minimum number of degree of freedom of a system is zero (B) Degree of freedom of a system containing a gaseous mixture of helium, carbon ... ) Enthalpy and internal energy change is zero during phase change processes like melting, vaporisation and sublimation
Last Answer : (D) Enthalpy and internal energy change is zero during phase change processes like melting, vaporisation and sublimation
Description : What refers to any change that a system undergoes from one equilibrium state to another equilibrium state? A. Process B. Path C. Phase D. Cycle
Last Answer : Process
Description : A system is in ______ equilibrium of its chemical composition does not change with time, i.e., no chemical reaction occurs. A. Chemical B. Thermal C. Mechanical D. Phase
Last Answer : Chemical
Description : In order to make a phase change from liquid to gas you must add energy equal to the what of vaporization?
Last Answer : Need answer
Description : Filling of gas from a high pressure cylinder into small bottles is an example of a/an __________ process. (A) Equilibrium (B) Adiabatic (C) Steady (D) Unsteady
Last Answer : (D) Unsteady
Description : An example of sample preparation in bioanalysis is __________________? A. Solid-solid extraction B. Solid-liquid extraction C. Liquid-solid extraction D. Solid-phase extraction
Last Answer : D. Solid-phase extraction
Description : At equilibrium the concentration of water in vapour phase (C* ) in kg/m3 of air space and the amount of water (m) adsorbed per kg of dry silica gel are related by, C* = 0.0667m. To maintain dry conditions in a room ... which the temperature is maintained constant) is (A) 0.0 (B) 0.2 (C) 0.4 (D) 1.0
Last Answer : (C) 0.4
Description : If in the gaseous phase reaction, N2O4 ⇌ 2NO2 , x is the part of N2O4 which dissociates, then the number of molecules at equilibrium will be (A) (1 + x) (B) (1 - x) (C) (1 + x) 2 (D) (1 - x)
Last Answer : (A) (1 + x)
Description : In the gaseous phase ammonia formation reaction (N2 + 3H2 ⇌ 2NH3 ), the value of the equilibrium constant depends on the (A) Total pressure of the system (B) Volume of the reactor (C) Temperature (D) Initial concentration of N2 and H2
Last Answer : (C) Temperature
Description : In which of the following gaseous phase reactions, the equilibrium of the reaction remains unaffected by pressure changes? (A) 2O3 ⇌ 3O2 (B) N2 + O2 ⇌ 2NO (C) 2NO2 ⇌ N2O4 (D) 2SO2 + O2 ⇌ 2SO3
Last Answer : (B) N2 + O2 ⇌ 2NO
Description : Number of degrees of freedom for a three phase system in equilibrium comprising of three non-reacting chemical species is (A) 2 (B) 0 (C) 1 (D) 3
Last Answer : (A) 2
Description : The necessary condition for phase equilibrium in a multiphase system of N components is that the (A) Chemical potentials of a given component should be equal in all phases (B) Chemical potentials of all ... potentials of any given component in all the phases should be the same (D) None of these
Last Answer : (A) Chemical potentials of a given component should be equal in all phases
Description : The necessary and sufficient condition for equilibrium between two phases is (A) The concentration of each component should be same in the two phases (B) The temperature of each phase should be same ( ... the two phases (D) The chemical potential of each component should be same in the two phases
Last Answer : (D) The chemical potential of each component should be same in the two phases
Description : For the gaseous phase chemical reaction, C2H4(g) + H2O(g) ↔ C2H5OH(g), the equilibrium conversion does not depend on the (A) Steam to ethylene ratio (B) Temperature (C) Pressure (D) None of these
Last Answer : (D) None of these
Description : What refers to the pressure at which a pure substance changes phase at a given temperature? A. Equilibrium pressure B. Saturation pressure C. Superheated pressure D. Subcooled pressure
Last Answer : Saturation pressure
Description : What refers to the temperature at which a pure substance changes phase at a given pressure? A. Equilibrium temperature B. Saturation temperature C. Superheated temperature D. Subcooled temperature
Last Answer : Saturation temperature
Description : What is the state at which all three phases of water coexist in equilibrium? A. Tripoint of water B. Triple point of water C. Triple phase point of water D. Phase point of water
Last Answer : Triple point of water
Description : A system is said to be in thermodynamic equilibrium if it maintains ______ equilibrium. A. Mechanical and phase B. Thermal and chemical C. Thermal, mechanical and chemical D. Thermal, phase, mechanical and chemical
Last Answer : Thermal, phase, mechanical and chemical
Description : What is a process in which the system remains infinitesimally closed to an equilibrium state at all times? A. Path equilibrium process B. Cycle equilibrium process C. Phase equilibrium process D. Quasi-state or quasiequilibrium process
Last Answer : Quasi-state or quasi- equilibrium process
Description : If a system involves two phases, it is in ______ equilibrium when the mass of each phase reaches an equilibrium level and stays there. A. Chemical B. Thermal C. Mechanical D. Phase
Last Answer : Phase
Description : A system is in ______ equilibrium if the temperature is the same throughout the entire system. A. Static B. Thermal C. Mechanical D. Phase
Last Answer : Thermal
Description : In case of steam distillation, the steam leaving the liquid is not completely saturated with distillate vapour, because (A) Temperature is less (B) Total pressure is less (C) Mixing of steam ... not so intimate as to result in equilibrium condition (D) Saturated steam is used for steam distillation
Last Answer : (C) Mixing of steam with the material being vaporised is not so intimate as to result in equilibrium condition
Description : Moisture in a substance exerting an equilibrium vapour pressure less than that of pure liquid at the same temperature is called the __________ moisture. (A) Bound (B) Unbound (C) Critical (D) None of these
Last Answer : (A) Bound
Description : In a liquid-liquid extraction, 10 kg of a solution containing 2 kg of solute C and 8 kg of solvent A is brought into contact with 10 kg of solvent B. Solvent A and B are completely immiscible in each other whereas ... (C) Less than 1 kg of C is transferred to B (D) No amount of C is transferred to B
Last Answer : (A) The entire amount of C is transferred to solvent B
Description : The equilibrium liquid composition compared to the vapor composition in case of Azeotropic mixture is (A) More (B) Less (C) Same (D) Either more or less; depends on the system
Last Answer : (C) Same
Description : Compound A is extracted from a solution of A + B into a pure solvent S. A Co-current unit is used for the liquid-liquid extraction. The inlet rate of the solution containing A is 200 moles of B/hr.m2 and the ... extraction achieved in the unit is (A) 25% (B) 50% (C) 70% (D) 90%
Last Answer : (B) 50%
Description : In Azeotropic mixture, the equilibrium vapour composition is (A) More than liquid composition (B) Less than liquid composition (C) Same as liquid composition (D) Independent of pressure
Last Answer : (C) Same as liquid composition
Description : Bound moisture is that liquid which exerts an equilibrium vapor pressure __________ that of the pure liquid at the given temperature. (A) Less than (B) More than (C) Equal to (D) Either (A) or (B); depends on the solid
Last Answer : (A) Less than
Description : The minimum liquid rate to be used in an absorber corresponds to an operating line (A) Of slope = 1 (B) Of slope = 0.1 (C) Tangential to the equilibrium curve (D) None of these
Last Answer : (C) Tangential to the equilibrium curve