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)

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)
by

1 Answer

Answer :

(D) All (A), (B), and (C)
by

Related questions

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

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

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

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

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-efficient and fi° is the fugacity of the pure component i. the Ki value (Yi = Ki xi) is therefore, in general a function of (A) Temperature only (B) Temperature and pressure only (C) Temperature, pressure and liquid composition xi only (D) Temperature, pressure, liquid composition xi and vapour composition yi

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

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

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

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

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

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

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

Pick out the wrong statement. (A) Activity co-efficient is dimensionless. (B) In case of an ideal gas, the fugacity is equal to its pressure. (C) In a mixture of ideal gases, the fugacity of a component is equal to the partial pressure of the component. (D) The fugacity co-efficient is zero for an ideal gas

Description : Pick out the wrong statement. (A) Activity co-efficient is dimensionless. (B) In case of an ideal gas, the fugacity is equal to its pressure. (C) In a mixture of ideal gases, the fugacity of ... equal to the partial pressure of the component. (D) The fugacity co-efficient is zero for an ideal gas

Last Answer : (D) The fugacity co-efficient is zero for an ideal gas

Free energy, fugacity and activity co-efficient are all affected by change in the temperature. The fugacity co-efficient of a gas at constant pressure ____with the increase of reduced temperature. (A) Decreases (B) Increases (C) Remains constant

Description : Free energy, fugacity and activity co-efficient are all affected by change in the temperature. The fugacity co-efficient of a gas at constant pressure ____with the increase of reduced temperature. (A) Decreases (B) Increases (C) Remains constant

Last Answer : (B) Increases

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

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

Partial molar free energy of an element A in solution is same as its (A) Chemical potential (B) Activity (C) Fugacity (D) Activity co-efficient

Description : Partial molar free energy of an element A in solution is same as its (A) Chemical potential (B) Activity (C) Fugacity (D) Activity co-efficient

Last Answer : (A) Chemical potential

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

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

Which of the following is affected by the temperature? (A) Fugacity (B) Activity co-efficient (C) Free energy (D) All (A), (B) & (C)

Description : Which of the following is affected by the temperature? (A) Fugacity (B) Activity co-efficient (C) Free energy (D) All (A), (B) & (C)

Last Answer : (D) All (A), (B) & (C)

For an ideal liquid solution, which of the following is unity? (A) Activity (B) Fugacity (C) Activity co-efficient (D) Fugacity co-efficient

Description : For an ideal liquid solution, which of the following is unity? (A) Activity (B) Fugacity (C) Activity co-efficient (D) Fugacity co-efficient

Last Answer : (C) Activity co-efficient

With increase in reduced temperature, the fugacity co-efficient of a gas at constant reduced pressure (A) Increases (B) Decreases (C) Remain same (D) Decreases linearly

Description : With increase in reduced temperature, the fugacity co-efficient of a gas at constant reduced pressure (A) Increases (B) Decreases (C) Remain same (D) Decreases linearly

Last Answer : (A) Increases

Fugacity of a component in an ideal gas mixture is equal to the partial pressure of that component in the mixture. The fugacity of each component in a stable homogeneous solution at constant pressure and temperature __________ as its mole fraction increases. (A) Decreases (B) Decreases exponentially (C) Increases (D) Remain constant

Description : Fugacity of a component in an ideal gas mixture is equal to the partial pressure of that component in the mixture. The fugacity of each component in a stable homogeneous solution at constant pressure and ... increases. (A) Decreases (B) Decreases exponentially (C) Increases (D) Remain constant

Last Answer : (C) Increases

Which of the following is not affected by temperature changes? (A) Fugacity (B) Activity co-efficient (C) Free energy (D) None of these

Description : Which of the following is not affected by temperature changes? (A) Fugacity (B) Activity co-efficient (C) Free energy (D) None of these

Last Answer : (D) None of these

In an ideal solution, the activity of a component equals its (A) Mole fraction (B) Fugacity at the same temperature and pressure (C) Partial pressure (D) None of these

Description : In an ideal solution, the activity of a component equals its (A) Mole fraction (B) Fugacity at the same temperature and pressure (C) Partial pressure (D) None of these

Last Answer : (A) Mole fraction

For a stable phase at constant pressure and temperature, the fugacity of each component in a binary system __________ as its mole fraction increases. (A) Decreases (B) Increases (C) Remain same (D) Decreases linearly

Description : For a stable phase at constant pressure and temperature, the fugacity of each component in a binary system __________ as its mole fraction increases. (A) Decreases (B) Increases (C) Remain same (D) Decreases linearly

Last Answer : (B) Increases

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 increases (B) Solubility increases as temperature decreases (C) Solubility is independent of temperature (D) Solubility increases or decreases with temperature depending on the Gibbs free energy change of solution

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

“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

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

In a homogeneous solution, the activity co-efficient of a component depends upon the (A) Pressure (B) Composition (C) Temperature (D) All (A), (B) and (C)

Description : In a homogeneous solution, the activity co-efficient of a component depends upon the (A) Pressure (B) Composition (C) Temperature (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Specific __________ does not change during phase change at constant temperature and pressure. (A) Entropy (B) Gibbs energy (C) Internal energy (D) Enthalpy

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

Out of the following four assumptions used in the derivation of theequation for LMTD[LMTD = (∆t1- ∆t2)/ln(∆t1/∆t2)], which one is subject to the largest deviationin practice ?(A) Constant overall heat transfer co-efficient.(B) Constant rate of fluid flow(C) Constant specific heat(D) No partial phase change in the system

Description : Out of the following four assumptions used in the derivation of theequation for LMTD [LMTD = (∆t1 - ∆t2 )/ln(∆t1 /∆t2 )], which one is subject to the largest deviation in practice ? (A) Constant ... (B) Constant rate of fluid flow (C) Constant specific heat (D) No partial phase change in the system

Last Answer : (B) Constant rate of fluid flow

At 60° C, vapour pressure of methanol and water are 84.562 kPa and 19.953 kPa respectively. An aqueous solution of methanol at 60° C exerts a pressure of 39.223 kPa; the liquid phase and vapour phase mole fractions of methanol are 0.1686 and 0.5714 respectively. Activity co-efficient of methanol is (A) 1.572 (B) 1.9398 (C) 3.389

Description : At 60° C, vapour pressure of methanol and water are 84.562 kPa and 19.953 kPa respectively. An aqueous solution of methanol at 60° C exerts a pressure of 39.223 kPa; the liquid phase and vapour phase mole ... respectively. Activity co-efficient of methanol is (A) 1.572 (B) 1.9398 (C) 3.389

Last Answer : (A) 1.572

Activity co-efficient is a measure of the (A) Departure from ideal solution behaviour (B) Departure of gas phase from ideal gas law (C) Vapour pressure of liquid (D) None of these

Description : Activity co-efficient is a measure of the (A) Departure from ideal solution behaviour (B) Departure of gas phase from ideal gas law (C) Vapour pressure of liquid (D) None of these

Last Answer : (A) Departure from ideal solution behaviour

In a homogeneous solution, the fugacity of a component depends upon the (A) Pressure (B) Composition (C) Temperature (D) All (A), (B) and (C)

Description : In a homogeneous solution, the fugacity of a component depends upon the (A) Pressure (B) Composition (C) Temperature (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

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)

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

For water at 300°C, it has a vapour pressure 8592.7 kPa and fugacity 6738.9 kPa Under these conditions, one mole of water in liquid phase has a volume of 25.28 cm3 and that in vapour phase in 391.1 cm3.Fugacity of water (in kPa) at 9000 kPa will be (A) 6738.9 (B) 6753.5 (C) 7058.3 (D) 9000

Description : For water at 300°C, it has a vapour pressure 8592.7 kPa and fugacity 6738.9 kPa Under these conditions, one mole of water in liquid phase has a volume of 25.28 cm3 and that in vapour phase in 391.1 cm3.Fugacity of water (in kPa) at 9000 kPa will be (A) 6738.9 (B) 6753.5 (C) 7058.3 (D) 9000

Last Answer : (B) 6753.5

In an ideal gas mixture, fugacity of a species is equal to its (A) Vapor pressure (B) Partial pressure (C) Chemical potential (D) None of these

Description : In an ideal gas mixture, fugacity of a species is equal to its (A) Vapor pressure (B) Partial pressure (C) Chemical potential (D) None of these

Last Answer : (B) Partial pressure

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

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

For a given substance at a specified temperature, activity is __________ to fugacity. (A) Directly proportional (B) Inversely proportional (C) Equal (D) None of these

Description : For a given substance at a specified temperature, activity is __________ to fugacity. (A) Directly proportional (B) Inversely proportional (C) Equal (D) None of these

Last Answer : (A) Directly proportional

The standard state of a gas (at a given temperature) is the state in which fugacity is equal to (A) Unity (B) Activity (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : The standard state of a gas (at a given temperature) is the state in which fugacity is equal to (A) Unity (B) Activity (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

________ Equation predicts the activity co-efficient from experimental data. (A) Lewis-Randall (B) Margules (C) Van Laar (D) Both (B) & (C)

Description : ________ Equation predicts the activity co-efficient from experimental data. (A) Lewis-Randall (B) Margules (C) Van Laar (D) Both (B) & (C)

Last Answer : (D) Both (B) & (C)

Diffusion co-efficient of a metal in a solid solution depends upon its (A) Composition (B) Temperature (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : Diffusion co-efficient of a metal in a solid solution depends upon its (A) Composition (B) Temperature (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

A thin, flat & square plate measuring 2 m × 2 m is freely hanging in ambient air at 25°C. It is exposed to the solar radiation falling on one side of the plate at the rate of 500 W/m2. The plate temperature will remain constant at 30°C, if the convective heat transfer co-efficient is __________ W/m2 °C. (A) 50 (B) 100 (C) 150 (D) 200

Description : A thin, flat & square plate measuring 2 m 2 m is freely hanging in ambient air at 25°C. It is exposed to the solar radiation falling on one side of the plate at the rate of 500 W/m2. The plate temperature will ... heat transfer co-efficient is __________ W/m2 °C. (A) 50 (B) 100 (C) 150 (D) 200

Last Answer : (B) 100

During dehumidification of unsaturated air wet bulb temperature & partial pressure of vapor are not constant. However, during evaporative cooling process with recirculated water supply, the __________ remains constant. (A) Wet bulb temperature (B) Partial pressure of water vapor (C) Relative humidity (D) None of these

Description : During dehumidification of unsaturated air wet bulb temperature & partial pressure of vapor are not constant. However, during evaporative cooling process with recirculated water supply, the __________ remains ... pressure of water vapor (C) Relative humidity (D) None of these

Last Answer : (A) Wet bulb temperature

Log mean temperature difference (LMTD) cannot be used, if (A) Heat transfer co-efficient over the entire heat exchanger is not constant (B) There exists an unsteady state (C) The heat capacity is not constant and there is a phase change (D) None of these

Description : Log mean temperature difference (LMTD) cannot be used, if (A) Heat transfer co-efficient over the entire heat exchanger is not constant (B) There exists an unsteady state (C) The heat capacity is not constant and there is a phase change (D) None of these

Last Answer : (D) None of these

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)

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)

Gibbs free energy at constant pressure and temperature under equilibrium conditions is (A) ∞ (B) 0 (C) Maximum (D) Minimum

Description : Gibbs free energy at constant pressure and temperature under equilibrium conditions is (A) ∞ (B) 0 (C) Maximum (D) Minimum

Last Answer : (D) Minimum

Gibbs free energy of mixing at constant pressure and temperature is always (A) 0 (B) ∞ (C) + ve (D) - ve

Description : Gibbs free energy of mixing at constant pressure and temperature is always (A) 0 (B) ∞ (C) + ve (D) - ve

Last Answer : (D) - ve

Penetration theory relates the average mass transfer co-efficient (K) with diffusivity (D) as (A) K ∝D (B) K ∝√D (C) K ∝D1.5 (D) K ∝D

Description : Penetration theory relates the average mass transfer co-efficient (K) with diffusivity (D) as (A) K ∝D (B) K ∝√D (C) K ∝D1.5 (D) K ∝D

Last Answer : (B) K ∝√D

Which of the following equations is used for the prediction of activity co-efficient from experiments? (A) Van Laar equation (B) Margules equation (C) Wilson's equation (D) All (A), (B) and (C)

Description : Which of the following equations is used for the prediction of activity co-efficient from experiments? (A) Van Laar equation (B) Margules equation (C) Wilson's equation (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Pick out the wrong statement. (A) In a batch reactor, which is exclusively used for liquid phase reactions; temperature pressure and composition may vary with time (B) In a semi-batch reactor, one reactant is charged batch wise, while the other reactant is fed continuously (C) In a continuous flow reactor, uniform concentration cannot be maintained throughout the vessel even in a well agitated system (D) In a continuous flow reactor, both the reactants and the products flow out continuously

Description : Pick out the wrong statement. (A) In a batch reactor, which is exclusively used for liquid phase reactions; temperature pressure and composition may vary with time (B) In a semi-batch reactor, ... system (D) In a continuous flow reactor, both the reactants and the products flow out continuously

Last Answer : (C) In a continuous flow reactor, uniform concentration cannot be maintained throughout the vessel even in a well agitated system

The equation Tds = dE - PdV applies to (A) Single phase fluid of varying composition (B) Single phase fluid of constant composition (C) Open as well as closed systems (D) Both (B) and (C)

Description : The equation Tds = dE - PdV applies to (A) Single phase fluid of varying composition (B) Single phase fluid of constant composition (C) Open as well as closed systems (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

The equation Tds = dE - PdV applies to (A) Single phase fluid of varying composition (B) Single phase fluid of constant composition (C) Open as well as closed systems (D) Both (B) and (C)

Description : The equation Tds = dE - PdV applies to (A) Single phase fluid of varying composition (B) Single phase fluid of constant composition (C) Open as well as closed systems (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

The activity co-efficient of the solute in a dilute solution (A) Decreases with the increase of concentration of the solute (B) Increases with the increase of concentration of the solute (C) Remains constant (D) Is unity at infinite dilution

Description : The activity co-efficient of the solute in a dilute solution (A) Decreases with the increase of concentration of the solute (B) Increases with the increase of concentration of the solute (C) Remains constant (D) Is unity at infinite dilution

Last Answer : (C) Remains constant

__________ is concerned with the adsorption equilibria. (A) Fick's law (B) Gibb's equation (C) Freundlich equation (D) None of these

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

__________ equation relates the thermal conductivity of a solid to its temperature. (A) Antoine (B) Kopp's (C) Lee's (D) Kistyakowsky

Description : __________ equation relates the thermal conductivity of a solid to its temperature. (A) Antoine (B) Kopp's (C) Lee's (D) Kistyakowsky

Last Answer : (C) Lee's

Pick out the wrong statement. (A) The mole fraction of solute is directly proportional to the molality of a 'dilute' solution (B) For a non-reacting binary mixture of ideal gases, the partial pressure distribution of both components is nonlinear in the case of steady state unimolal unidirectional diffusion (C) Azeotropes obey Raoult's law at all temperature (D) The relative volatility of a binary mixture at the Azeotropic composition is 1

Description : Pick out the wrong statement. (A) The mole fraction of solute is directly proportional to the molality of a 'dilute' solution (B) For a non-reacting binary mixture of ideal gases, the partial ... at all temperature (D) The relative volatility of a binary mixture at the Azeotropic composition is 1

Last Answer : (C) Azeotropes obey Raoult's law at all temperature

The partial molar enthalpy of a component in an ideal binary gas mixture of composition Z, at a temperature T and pressure P, is a function only of (A) T (B) T and P (C) T, P and Z (D) T and Z

Description : The partial molar enthalpy of a component in an ideal binary gas mixture of composition Z, at a temperature T and pressure P, is a function only of (A) T (B) T and P (C) T, P and Z (D) T and Z

Last Answer : (B) T and P