Description : At constant temperature and pressure, for one mole of a pure substance, the ratio of the free energy to the chemical potential is (A) Zero (B) One (C) Infinity (D) Negative
Last Answer : (B) One
Description : When the number of sides of a polygon tends to infinity, it approaches _______.
Last Answer : When the number of sides of a polygon tends to infinity, it approaches _______.
Description : Pick out the wrong statement. (A) The vessel dispersion number (D/UL) for plug flow and mixed flow approaches zero and infinity respectively (B) Space time in a flow reactor is a ... ideal tubular flow reactor, mixing takes place in radial direction and there is no mixing in longitudinal direction
Last Answer : (C) Mixed reactor is always smaller than the plug flow reactor for all positive reaction orders for a particular duty
Description : The change in Gibbs free energy for vaporisation of a pure substance is (A) Positive (B) Negative (C) Zero (D) May be positive or negative
Last Answer : (C) Zero
Description : In fluid flow, cavitation is caused, if the (A) Fluid velocity decreases to zero (B) Total energy decreases (C) Both (A) and (B) (D) Flow pressure approaches its vapor pressure at the prevailing temperature
Last Answer : (D) Flow pressure approaches its vapor pressure at the prevailing temperature
Description : As the temperature is lowered towards the absolute zero, the value of ∂(∆F)/∂T, then approaches (A) Unity (B) Zero (C) That of the heat of reaction (D) Infinity
Last Answer : B) Zero
Description : Thermal efficiency of a Carnot engine can approach 100%, only when the temperature of the (A) Cold reservoir approaches zero (B) Hot reservoir approaches infinity (C) Either (A) or (B) (D) Neither (A) nor (B)
Last Answer : C) Either (A) or (B)
Description : As the temperature is lowered towards the absolute zero, the value of the quantity (∂∆F/∂T) approaches (A) Zero (B) Unity (C) Infinity (D) None of these
Last Answer : (A) Zero
Description : Specific __________ does not change during phase change at constant temperature and pressure. (A) Entropy (B) Gibbs energy (C) Internal energy (D) Enthalpy
Last Answer : (B) Gibbs energy
Description : Gibbs free energy at constant pressure and temperature under equilibrium conditions is (A) ∞ (B) 0 (C) Maximum (D) Minimum
Last Answer : (D) Minimum
Description : Gibbs free energy of mixing at constant pressure and temperature is always (A) 0 (B) ∞ (C) + ve (D) - ve
Last Answer : (D) - ve
Description : Pressure-enthalpy chart is useful in refrigeration. The change in internal energy of an ideal fluid used in ideal refrigeration cycle is (A) Positive (B) Negative (C) Zero (D) Infinity
Last Answer : C) Zero
Description : The relation connecting the fugacities of various components in a solution with one another and to composition at constant temperature and pressure is called the __________ equation. (A) Gibbs-Duhem (B) Van Laar (C) Gibbs-Helmholtz (D) Margules
Last Answer : (A) Gibbs-Duhem
Description : Gibbs-Duhem equation relates composition in liquid phase and the __________ at constant temperature & pressure. (A) Fugacity (B) Partial pressure (C) Activity co-efficient (D) All (A), (B), and (C)
Last Answer : (D) All (A), (B), and (C)
Description : The radius of circle tends to zero then it approaches a ________.
Last Answer : The radius of circle tends to zero then it approaches a ________.
Description : Specific/molar Gibbs free energy for a pure substance does not change during (A) Sublimation (B) Vaporisation (C) Melting (D) Either (A), (B) or (C)
Last Answer : (D) Either (A), (B) or (C)
Description : Gibbs free energy per mole for a pure substance is equal to the (A) Latent heat of vaporisation (B) Chemical potential (C) Molal boiling point (D) Heat capacity
Last Answer : (B) Chemical potential
Description : What is the entropy of a pure substance at a temperature of absolute zero? a. unity b. zero c. infinity d. undefined
Last Answer : zero
Description : “The fugacity of a gas in a mixture is equal to the product of its mole fraction and its fugacity in the pure state at the total pressure of the mixture". This is (A) The statement as per Gibbs-Helmholtz (B) Called Lewis-Randall rule (C) Henry's law (D) None of these
Last Answer : (B) Called Lewis-Randall rule
Description : Gibbs-Duhem equation (A) States that n1dμ1 + n2dμ2 + ....njdμj = 0, for a system of definite composition at constant temperature and pressure (B) Applies only to binary systems (C) Finds no application in gas-liquid equilibria involved in distillation (D) None of these
Last Answer : (A) States that n1dμ1 + n2dμ2 + ....njdμj = 0, for a system of definite composition at constant temperature and pressure
Description : If the heat of solution of an ideal gas in a liquid is negative, then its solubility at a given partial pressure varies with the temperature as (A) Solubility increases as temperature ... (D) Solubility increases or decreases with temperature depending on the Gibbs free energy change of solution
Last Answer : (B) Solubility increases as temperature decreases
Description : The standard Gibbs free energy change of a reaction depends on the equilibrium (A) Pressure (B) Temperature (C) Composition (D) All (A), (B) and (C)
Last Answer : (B) Temperature
Description : Pick out the wrong statement. (A) The controlling resistance in case of heating of air by condensing steam is in the air film (B) The log mean temperature difference (LMTD) for ... a pure fluid at a given pressure from liquid to vapor or vice-versa occurs at saturation temperature
Last Answer : (C) In case of a 1 - 2 shell and tube heat exchanger, the LMTD correction factor value increases sharply, when a temperature cross occurs
Description : The molar excess Gibbs free energy, gE, for a binary liquid mixture at T and P is given by, (gE/RT) = A . x1. x2, where A is a constant. The corresponding equation for ln y1, where y1is the activity co-efficient of component 1, is (A) A . x22 (B) Ax1 (C) Ax2 (D) Ax12
Last Answer : (A) A . x22
Description : The hydrodynamic and thermal boundary layers will merge, when (A) Prandtl number is one (B) Schmidt number tends to infinity (C) Nusselt number tends to infinity (D) Archimedes number is greater than 10000
Last Answer : (A) Prandtl number is one
Description : Variation of equilibrium pressure with temperature for any two phases of a given substances is given by the __________ equation. (A) Gibbs-Duhem (B) Maxwell's (C) Clapeyron (D) None of these
Last Answer : (C) Clapeyron
Description : Chemical potential (an intensive property) of a substance is a force that drives the chemical system to equilibrium and is equal to its partial molar properties. The ratio of chemical potential to free energy of a pure substance ... temperature and pressure is (A) 0 (B) 1 (C) ∞ (D) None of these
Last Answer : (B) 1
Description : If a gas is heated against a pressure, keeping the volume constant, then work done will be equal to (a) + v (b) – ve (c) zero (d) pressure x volume (e) any where between zero and infinity.
Last Answer : Answer : c
Description : In any spontaneous process, the __________ free energy decreases. (A) Helmholtz (B) Gibbs (C) Both ‘a’ & ‘b’ (D) Neither 'a' nor 'b'
Last Answer : (C) Both ‘a’ & ‘b’
Description : Specific __________ does not change during a phase change (e.g. sublimation, melting, vaporisation etc.). (A) Entropy (B) Internal energy (C) Enthalpy (D) Gibbs free energy
Last Answer : (D) Gibbs free energy
Description : The change in __________ is equal to the reversible work for compression in steady state flow process under isothermal condition. (A) Internal energy (B) Enthalpy (C) Gibbs free energy (D) Helmholtz free energy
Last Answer : (C) Gibbs free energy
Description : Pick out the wrong statement. (A) The net change in entropy in any reversible cycle is always zero (B) The entropy of the system as a whole in an irreversible process increases (C) The ... to a maximum (D) The entropy of a substance does not remain constant during a reversible adiabatic change
Last Answer : (D) The entropy of a substance does not remain constant during a reversible adiabatic change
Description : Cp of a gas at its critical temperature and pressure (A) Becomes zero (B) Becomes infinity (C) Equals 1 kcal/kmol °K (D) Equals 0.24 kcal/kmol °K
Last Answer : (B) Becomes infinity
Description : In an incompressible flow of fluid, the fluid (A) Temperature remains constant (B) Compressibility is greater than zero (C) Density does not change with pressure & temperature (D) Is frictionless
Last Answer : (C) Density does not change with pressure & temperature
Description : Boiling of liquid is accompanied with increase in the (A) Vapor pressure (B) Specific Gibbs free energy (C) Specific entropy (D) All (A), (B) and (C)
Last Answer : (A) Vapor pressure
Description : Pick out the wrong statement: (A) With change in temperature, the radiant energy emitted by a black body remains unchanged (B) Absorptivity of a body approaches unity in case of diffuse reflection (C) Absorptivity of ... unity (D) Value of Stefan-Boltzmann constant is 4.876 10 -8 KCal/m2 .hr.°K4
Last Answer : (A) With change in temperature, the radiant energy emitted by a black body remains unchanged
Description : The temperature shown for a given pressure rating by class is normally? a) The temperature of the flanged fitting. b) The temperature of the process fluid within. c) The process temperature minus 20°F. d) A and B.
Last Answer : d) A and B.
Description : A chemical reaction will occur spontaneously at constant pressure and temperature, if the free energy is (A) Zero (B) Positive (C) Negative (D) None of these
Last Answer : (C) Negative
Description : The efficiency of Diesel cycle approaches to Otto cycle efficiency when A. cut-off is increased B. cut-off is decreased C. cut-off is zero D. cut-off is constant
Last Answer : Answer: C
Description : In fluid flow, the stagnation point is defined as a point, where the __________ is zero. (A) Flow velocity (B) Pressure (C) Total energy (D) All (A), (B) and (C)
Last Answer : (A) Flow velocity
Description : When a gas is expanded from high pressure region to low pressure region; temperature change occurs". This phenomenon is related to the (A) Gibbs-Duhem equation (B) Gibbs-Helmholtz equation (C) Third law of thermodynamics (D) Joule-Thomson effect
Last Answer : (D) Joule-Thomson effect
Description : Equation which relates pressure, volume and temperature of a gas is called the (A) Equation of state (B) Gibbs Duhem equation (C) Ideal gas equation (D) None of these
Last Answer : (A) Equation of state
Description : Dielectric constant of vacuum is (A) infinity. (B) 100. (C) one. (D) zero.
Last Answer : (C) one.
Description : In a parallel flow heat exchanger, if the outlet temperature of hot and cold fluids are the same, then the log mean temperature difference (LMTD) is (A) Minimum (B) Maximum (C) Zero (D) Infinity
Description : The surface tension of a liquid, at critical temperature is (A) Indeterminate (B) Zero (C) Infinity (D) Same as that at any other temperature
Last Answer : Option B
Description : Moisture in a solid exerting an equilibrium vapour pressure equal to that of the pure liquid at the same temperature is called the __________ moisture. (A) Unbound (B) Critical (C) Free (D) Bound
Last Answer : (A) Unbound
Description : (∂H/∂T)P is the mathematical expression for (A) CV (B) Entropy change (C) Gibbs free energy (D) None of these
Last Answer : (D) None of these
Description : Gibbs free energy (G) is represented by, G = H - TS, whereas Helmholtz free energy, (A) is given by, A = E - TS. Which of the following is the Gibbs Helmholtz equation? (A) [∂(G/T)/∂T] = - (H/T2) (B) [∂(A/T)/∂T]V = - E/T2 (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : _________ does not change during phase transformation processes like sublimation, melting & vaporisation. (A) Entropy (B) Gibbs free energy (C) Internal energy (D) All (A), (B) & (C)
Last Answer : (B) Gibbs free energy