Description : The four properties of a system viz. P, V, T, S are related by __________ equation. (A) Gibbs-Duhem (B) Gibbs-Helmholtz (C) Maxwell's (D) None of these
Last Answer : (C) Maxwell's
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 : 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 : 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 : 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 : Clausius-Clapeyron equation is applicable to __________ equilibrium processes. (A) Solid-vapor (B) Solid-liquid (C) Liquid-vapor (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : The equation relating E, P, V and T which is true for all substances under all conditions is given by (∂E/∂V)T = T(∂P/∂T)H - P. This equation is called the (A) Maxwell's equation (B) Thermodynamic equation of state (C) Equation of state (D) Redlich-Kwong equation of state
Last Answer : (B) Thermodynamic equation of state
Description : Clausius-Clapeyron Equation gives accurate result, when the (A) Vapour pressure is relatively low and the temperature does not vary over wide limits (B) Vapour obeys the ideal gas law and the latent heat of ... is negligible compared with that in the vapour state (D) All (A), (B) and (C)
Description : Clapeyron Equation deals with the (A) Rate of change of vapour pressure with temperature (B) Effect of an inert gas on vapour pressure (C) Calculation of ΔF for spontaneous phase change (D) Temperature dependence of heat of phase transition
Last Answer : (A) Rate of change of vapour pressure with temperature
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 : 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 : Clapeyron equation is a relation between (a) temperature, pressure and enthalpy (b) specific volume and enthalpy (c) temperature and enthalpy (d) temperature, pressure, specific vapour and enthalpy.
Last Answer : Ans: D
Description : For multi-component multiple phases to be in equilibrium at the same pressure and temperature, the __________ of each component must be same in all phases. (A) Chemical potential (B) Fugacity (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
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 : 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 : To obtain integrated form of Clausius-Clapeyron equation, ln (P2/P1) = (∆HV/R) (1/T1- 1/T2) from the exact Clapeyron equation, it is assumed that the (A) Volume of the liquid phase is negligible compared to ... gas (C) Heat of vaporisation is independent of temperature (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
Description : Clapeyron equation is applicable for registration at (a) saturation point of vapour (b) saturation point of liquid (c) sublimation temperature (d) triple point.
Last Answer : Ans: a
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 : __________ is concerned with the adsorption equilibria. (A) Fick's law (B) Gibb's equation (C) Freundlich equation (D) None of these
Last Answer : (C) Freundlich equation
Description : Which of the following is not an equation of state? (A) Bertholet equation (B) Clausius-Clapeyron equation (C) Beattie-Bridgeman equation (D) None of these
Last Answer : (B) Clausius-Clapeyron equation
Description : Pick out the Clausius-Clapeyron equation from the following: (A) dP/dT = ∆H/T∆V (B) ln P = - (∆H/RT) + constant (C) ∆F = ∆H + T [∂(∆F)/∂T]P (D) None of these
Last Answer : B) ln P = - (∆H/RT) + constant
Description : Pick out the wrong statement. (A) Enthalpies of all elements in their standard states are assumed to be zero (B) Combustion reactions are never endothermic in nature (C) Heat of reaction ... to the change in internal energy (D) Clausius-Clapeyron equation is not applicable to melting process
Last Answer : (D) Clausius-Clapeyron equation is not applicable to melting process
Description : Which of the following is Clausius-Clapeyron Equation for vaporisation of an ideal gas under the condition that the molar volume of liquid is negligible compared to that of the vapor? (A) d ln p/dt = Hvap/RT2 (B) d ln p/dt = RT2/Hvap (C) dp/dt = RT2/Hvap (D) dp/dt = Hvap/RT2
Last Answer : (A) d ln p/dt = Hvap/RT2
Description : Gibbs free energy of a pure fluid approaches __________ as the pressure tends to zero at constant temperature. (A) Infinity (B) Minus infinity (C) Zero (D) None of these
Last Answer : (B) Minus infinity
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 : 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 : 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)
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 : Arrhenius equation represents graphically the variation between the __________ and temperature. (A) Rate of reaction (B) Frequency factor (C) Rate constant (D) Activation energy
Last Answer : (C) Rate constant
Description : Arrhenius equation shows the variation of __________ with temperature. (A) Reaction rate (B) Rate constant (C) Energy of activation (D) Frequency factor
Last Answer : (B) Rate constant
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 : The variation of heat of reaction with temperature at constant pressure is given by the __________ law. (A) Kelvin's (B) Antoine’s (C) Kirchoff’s (D) None of these
Last Answer : (C) Kirchoff’s
Description : In which of the following forms can Maxwell’s equation not be represented? a) Static b) Differential c) Integral d) Harmonic
Last Answer : a) Static
Description : For structural analysis of forces, the method refers to (A) Moment-area-theorem (B) Three-moment equation (C) Maxwell's reciprocal theorem (D) None of these
Last Answer : (A) Moment-area-theorem
Description : In an interphase heat transfer process, the equilibrium state corresponds to equality of temperature in the two phases, while the condition for equilibrium in an interphase mass transfer process is ... B) Chemical potentials (C) Activity co-efficients (D) Mass transfer co-efficients
Last Answer : (A) Concentrations
Description : Solid and liquid phases of a substance are in equilibrium at the (A) Critical temperature (B) Melting point (C) Freezing point (D) Both (B) and (C)
Last Answer : D) Both (B) and (C)
Description : At equilibrium condition, the chemical potential of a material in different phases in contact with each other is equal. The chemical potential for a real gas (μ) is given by (where, μ = standard chemical potential at unit fugacity (f° = 1 atm. ... (B) μ°+ R ln f (C) μ° + T ln f (D) μ° + R/T ln f
Last Answer : (A) μ° + RT ln f
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 : Gibbs-Helmholtz equation is (A) ∆F = ∆H + T [∂(∆F)/∂T]P (B) ΔF = ΔH - TΔT (C) d(E - TS) T, V < 0 (D) dP/dT = ∆Hvap/T.∆Vvap
Last Answer : (A) ∆F = ∆H + T [∂(∆F)/∂T]P
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 : What refers to the heat needed to change the temperature of the substances without changing its phases? a. Latent heat b. Sensible heat c. Specific heat d. entropy
Last Answer : Sensible heat
Description : Which one of the following best defines the word allotropes ? A Different structural forms of an element B A pair of substances that differ by H+ C Elements that possess properties intermediate between ... a specific number of neutrons E The different phases (solid, liquid or gas) of a substance
Last Answer : A Different structural forms of an element
Description : "At the absolute zero temperature, the entropy of every perfectly crystalline substance becomes zero". This follows from the (A) Third law of thermodynamics (B) Second law of thermodynamics (C) Nernst heat theorem (D) Maxwell's relations
Last Answer : (A) Third law of thermodynamics
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 : he quantitative effect of temperature on chemical equilibrium is given by the (A) Van’t-Hoff equation (B) Le-Chatelier's principle (C) Arrhenius equation (D) None of these
Last Answer : (A) Van’t-Hoff equation
Description : Write A Short Note On Gibbs Free Energy And Derive The Equation For The Same.?
Last Answer : This thermodynamic quantity states that the decrease in value during a process is equal to the useful work done by the system. It is denoted by G and the mathematical equation is: G = H - TS Where ... of the system Thus the above equation becomes: ΔG = ΔH - TΔS is known as Gibbs-Helmoholtz equation.
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 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