The chemical potential of a component (μi) of a phase is the amount by which its capacity for doing all work, barring work of expansion is increased per unit amount of substance added for an infinitesimal addition at constant temperature and pressure. It is given by (A) (∂E/∂ni)S, v, nj (B) (∂G/∂ni)T, P, nj = (∂A/∂ni) T, v, nj (C) (∂H/∂ni)S, P, nj (D) All (A), (B) and (C)

The chemical potential of a component (μi) of a phase is the amount by
which its capacity for doing all work, barring work of expansion is increased per unit amount of substance added for an infinitesimal addition at constant temperature and pressure. It is given by
(A) (∂E/∂ni)S, v, nj
(B) (∂G/∂ni)T, P, nj = (∂A/∂ni) T, v, nj
(C) (∂H/∂ni)S, P, nj
(D) All (A), (B) and (C)
by

1 Answer

Answer :

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

Related questions

Chemical potential of ith component of a system is given by (A) µi = (∂F/∂ni)T, P, ni (B) µi = (∂A/∂ni)T, P, ni (C) µi = (∂F/∂ni)T, P (D) µi = (∂A/∂ni)T, P

Description : Chemical potential of ith component of a system is given by (A) µi = (∂F/∂ni)T, P, ni (B) µi = (∂A/∂ni)T, P, ni (C) µi = (∂F/∂ni)T, P (D) µi = (∂A/∂ni)T, P

Last Answer : A) µi = (∂F/∂ni)T, P, ni

Cvis given by (A) (∂E/∂T)V (B) (∂E/∂V)T (C) (∂E/∂P)V (D) (∂V/∂T)P

Description : Cvis given by (A) (∂E/∂T)V (B) (∂E/∂V)T (C) (∂E/∂P)V (D) (∂V/∂T)P

Last Answer : (A) (∂E/∂T)V

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

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

The amount of heat energy per kilogram that must be added or removed when a substance changes from one phase to another.  a. specific heat  b. heat of expansion  c. latent heat  d. useful heat

Description : The amount of heat energy per kilogram that must be added or removed when a substance changes from one phase to another.  a. specific heat  b. heat of expansion  c. latent heat  d. useful heat

Last Answer : latent heat

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

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

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

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

The ______ of a substance is the amount of heat that must be added or removed from a unit mass of the substance to change its temperature by one degree.  A. Latent heat of fusion  B. Molar heat  C. Specific heat capacity  D. Specific heat

Description : The ______ of a substance is the amount of heat that must be added or removed from a unit mass of the substance to change its temperature by one degree.  A. Latent heat of fusion  B. Molar heat  C. Specific heat capacity  D. Specific heat

Last Answer : Specific heat capacity

Joule-Thomson co-efficient which is defined as, η = (∂T/∂P)H = 1/Cp (∂H/∂T)P, changes sign at a temperature known as inversion temperature. The value of Joule-Thomson co-efficient at inversion temperature is (A) 0 (B) ∞ (C) +ve (D) -ve

Description : Joule-Thomson co-efficient which is defined as, η = (∂T/∂P)H = 1/Cp (∂H/∂T)P, changes sign at a temperature known as inversion temperature. The value of Joule-Thomson co-efficient at inversion temperature is (A) 0 (B) ∞ (C) +ve (D) -ve

Last Answer : (A) 0

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 (C) The pressure should be same in the two phases (D) The chemical potential of each component should be same in the two 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

A plot of pressure vs. temperature for a given substance showing the various phases possible for that particular substance.  a. Phase diagram  b. P-T diagram  c. Wein Diagram  d. Histogram

Description : A plot of pressure vs. temperature for a given substance showing the various phases possible for that particular substance.  a. Phase diagram  b. P-T diagram  c. Wein Diagram  d. Histogram

Last Answer : Phase diagram

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 at constant temperature and pressure is (A) 0 (B) 1 (C) ∞ (D) None of these

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

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

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

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

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

(∂H/∂T)P is the mathematical expression for (A) CV (B) Entropy change (C) Gibbs free energy(D) None of these

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

(∂E/∂T)V is the mathematical expression for (A) CV (B) Enthalpy change (C) Free energy change (D) None of these

Description : (∂E/∂T)V is the mathematical expression for (A) CV (B) Enthalpy change (C) Free energy change (D) None of these

Last Answer : (D) None of these

The equation DU = Tds - PdV is applicable to infinitesimal changes occuring in (A) An open system of constant composition (B) A closed system of constant composition (C) An open system with changes in composition (D) A closed system with changes in composition

Description : The equation DU = Tds - PdV is applicable to infinitesimal changes occuring in (A) An open system of constant composition (B) A closed system of constant composition (C) An open system with changes in composition (D) A closed system with changes in composition

Last Answer : (D) A closed system with changes in composition

Addition of heat at constant pressure to a gas results in  (a) raising its temperature  (b) raising its pressure  (c) raising its volume  (d) raising its temperature and doing external work  (e) doing external work.

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Last Answer : Answer : d

What ideal gas is stored in a container at constant volume. If the temperature (T) were increased to 3T what would be the change in pressure (P)?

Description : What ideal gas is stored in a container at constant volume. If the temperature (T) were increased to 3T what would be the change in pressure (P)?

Last Answer : Feel Free to Answer

Critical temperature is defined as the temperature above which a gas will (A) Not liquify (barring exceptions) (B) Immediately liquify (C) Never liquify however high the pressure may be (D) None of these

Description : Critical temperature is defined as the temperature above which a gas will (A) Not liquify (barring exceptions) (B) Immediately liquify (C) Never liquify however high the pressure may be (D) None of these

Last Answer : (C) Never liquify however high the pressure may be

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

For a perfect gas, according to Boyle’s law (where p = Absolute pressure, v = Volume, and T = Absolute temperature)  A. p v = constant, if T is kept constant  B. v/T = constant, if p is kept constant  C. p/T = constant, if v is kept constant  D. T/p = constant, if v is kept constant

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Last Answer : Answer: A

The amount of chemical coagulant added for treatment of polluted water __________ with increase in temperature of the polluted water to be treated. (A) Decreases (B) Increases (C) Remain constant (D) May increase or decrease; depends on the chemical characteristics of polluted water

Description : The amount of chemical coagulant added for treatment of polluted water __________ with increase in temperature of the polluted water to be treated. (A) Decreases (B) Increases (C) Remain constant (D) May increase or decrease; depends on the chemical characteristics of polluted water

Last Answer : (A) Decreases

Considering the endothermic dissociation of CaCO3 in a closed vessel (CaCO3 ⇌ CaO + CO2 ), the pressure of CO2 increases, if (A) A catalyst is added (B) The temperature is increased (C) An inert gas is pumped keeping the temperature constant (D) None of these

Description : Considering the endothermic dissociation of CaCO3 in a closed vessel (CaCO3 ⇌ CaO + CO2 ), the pressure of CO2 increases, if (A) A catalyst is added (B) The temperature is increased (C) An inert gas is pumped keeping the temperature constant (D) None of these

Last Answer : (B) The temperature is increased

During adiabatic expansion of gas (A) Pressure remains constant (B) Pressure is increased (C) Temperature remains constant (D) None of these

Description : During adiabatic expansion of gas (A) Pressure remains constant (B) Pressure is increased (C) Temperature remains constant (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)

The work done by a weightless piston in causing an expansing `Delta V` (at constant temperature), when the opposing pressure P is variable, is given b

Description : The work done by a weightless piston in causing an expansing `Delta V` (at constant temperature), when the opposing pressure P is variable, is given b

Last Answer : The work done by a weightless piston in causing an expansing `Delta V` (at constant temperature), when the opposing ... 0 C. `W = -P Delta V` D. None

Each term of the Bernoulli's equation written in the form, (p/ρ) + (g/gc ). Z + (v 2 /2gc ) = constant, represents the total energy per unit (A) Mass (B) Volume (C) Specific weight (D) None of these

Description : Each term of the Bernoulli's equation written in the form, (p/ρ) + (g/gc ). Z + (v 2 /2gc ) = constant, represents the total energy per unit (A) Mass (B) Volume (C) Specific weight (D) None of these

Last Answer : (A) Mass

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

Consider the following processes: [IES-1999] 1. Constant pressure heat addition. 2. Adiabatic compression. 3. Adiabatic expansion. 4. Constant pressure heat rejection. The correct sequence of these processes in Rankine cycle is: (a) 1, 2, 3, 4 (b) 2, 1, 4, 3 (c) 2, 1, 3, 4 (d) 1, 2, 4, 3

Description : Consider the following processes: [IES-1999] 1. Constant pressure heat addition. 2. Adiabatic compression. 3. Adiabatic expansion. 4. Constant pressure heat rejection. The correct sequence of these processes in Rankine cycle is: (a) 1, 2, 3, 4 (b) 2, 1, 4, 3 (c) 2, 1, 3, 4 (d) 1, 2, 4, 3

Last Answer : (c) 2, 1, 3, 4 

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.) and the gas behaves ideally.) (A) μ° + RT ln f (B) μ°+ R ln f (C) μ° + T ln f (D) μ° + R/T ln f

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

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

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

The heat Q per unit mass per degree change in temperature that must be supplied or removed to change the temperature of a substance.  a. Specific Heat Capacity  b. Latent Heat  c. Heat of Transformation  d. Internal Heat

Description : The heat Q per unit mass per degree change in temperature that must be supplied or removed to change the temperature of a substance.  a. Specific Heat Capacity  b. Latent Heat  c. Heat of Transformation  d. Internal Heat

Last Answer : Specific Heat Capacity

(1/V) (∂V/∂T)Pis the mathematical expression (A) Joule-Thomson co-efficient (B) Specific heat at constant pressure (Cp) (C) co-efficient of thermal expansion (D) Specific heat at constant volume (CV)

Description : (1/V) (∂V/∂T)Pis the mathematical expression (A) Joule-Thomson co-efficient (B) Specific heat at constant pressure (Cp) (C) co-efficient of thermal expansion (D) Specific heat at constant volume (CV)

Last Answer : (C) co-efficient of thermal expansion

In a constant pressure process steam is generated from 10 bar and 0.8 dry condition till it become dry and saturated. Determine amount of heat added per kg of steam. From steam table at 10 bar Tsat = 179.9°C hf = 762.6 kl/kg, hg = 2776.2 kJ/kg

Description : In a constant pressure process steam is generated from 10 bar and 0.8 dry condition till it become dry and saturated. Determine amount of heat added per kg of steam. From steam table at 10 bar Tsat = 179.9°C hf = 762.6 kl/kg, hg = 2776.2 kJ/kg 

Last Answer : Constant pressure process Final condition of steam is dry saturated Enthalpy of dry steam = hg= hf + hfg =2776.2 KJ/Kg .Given Latent heat of vaporization = hfg = hg - hf =2776.2-762.6 =2013.6 KJ/Kg Initial condition ... hfg = 762.6+0.8 X 2013.6 =2373.48 KJ/Kg Heat added = hg-hw = 402.72 KJ/kg

A process, in which the temperature of the working substance remains constant during its expansion or compression, is called  A. isothermal process  B. hyperbolic process  C. adiabatic process  D. polytropic process

Description : A process, in which the temperature of the working substance remains constant during its expansion or compression, is called  A. isothermal process  B. hyperbolic process  C. adiabatic process  D. polytropic process

Last Answer : Answer: A

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 of air space 100m3 containing 2.2 kg of water vapour initially, 10 kg of dry silica gel is kept in the room. The fraction of initial water remaining in the air space after a long time (during which the temperature is maintained constant) is (A) 0.0 (B) 0.2 (C) 0.4 (D) 1.0

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

In frictional fluid flow, the quantity, (P/ρ) + (V 2 /2gc) + gz/gc) is (A) Constant along a streamline (B) Not constant along a streamline (C) Increased in the direction of flow (D) None of these

Description : In frictional fluid flow, the quantity, (P/ρ) + (V 2 /2gc) + gz/gc) is (A) Constant along a streamline (B) Not constant along a streamline (C) Increased in the direction of flow (D) None of these

Last Answer : (B) Not constant along a streamline

The internal energy of a gas obeying P (V - b) RT (where, b is a positive constant and has a constant Cv ), depends upon its (A) Pressure (B) Volume (C) Temperature (D) All (A), (B) & (C)

Description : The internal energy of a gas obeying P (V - b) RT (where, b is a positive constant and has a constant Cv ), depends upon its (A) Pressure (B) Volume (C) Temperature (D) All (A), (B) & (C)

Last Answer : (C) Temperature

An ideal gas is heated at constant volume and then expanded isothermally. Show processes on P-V & T-S diagrams.

Description : An ideal gas is heated at constant volume and then expanded isothermally. Show processes on P-V & T-S diagrams.

Last Answer : Process 1-2 : Constant volume process Process 2-3 : Constant temperature process (Isothermal process)

In a Rankine cycle, regeneration results in higher efficiency because (a) Pressure inside the boiler increases [GATE-2003] (b) Heat is added before steam enters the low pressure turbine (c) Average temperature of heat addition in the boiler increases (d) Total work delivered by the turbine increases

Description : In a Rankine cycle, regeneration results in higher efficiency because (a) Pressure inside the boiler increases [GATE-2003] (b) Heat is added before steam enters the low pressure turbine (c) ... temperature of heat addition in the boiler increases (d) Total work delivered by the turbine increases 

Last Answer : (c) Average temperature of heat addition in the boiler increases  

Joule-Thomson co-efficient is defined as (A) µ = (∂P/∂T)H (B) µ = (∂T/∂P)H (C) µ = (∂E/∂T)H (D) µ = (∂E/∂P)H

Description : Joule-Thomson co-efficient is defined as (A) µ = (∂P/∂T)H (B) µ = (∂T/∂P)H (C) µ = (∂E/∂T)H (D) µ = (∂E/∂P)H

Last Answer : (B) µ = (∂T/∂P)H

Bernoulli's principle states that, for streamline motion of an incompressible non-viscous fluid: A. the pressure at any part + the kinetic energy per unit volume = constant B. the kinetic energy per unit volume + the potential energy per unit volume = constant C. the pressure at any part + the potential energy per unit volume = constanD. the pressure at any part + the kinetic energy per unit volume + the potential energy per unit volume = constantt

Description : Bernoulli's principle states that, for streamline motion of an incompressible non-viscous fluid: A. the pressure at any part + the kinetic energy per unit volume = constant B. the kinetic ... + the kinetic energy per unit volume + the potential energy per unit volume = constant

Last Answer : the pressure at any part + the kinetic energy per unit volume + the potential energy per unit volume = constant

In a reversible chemical reaction (where, Δx = number of moles of products-number of moles of reactants) (A) Addition of inert gas favours the forward reaction, when Δx is positive (B) Pressure has no effect on equilibrium, when Δn = 0 (C) Addition of inert gas has no effect on the equilibrium constant at constant volume for any value of Δx (+ ve, - ve) or zero) (D) All 'a', 'b' & 'c'

Description : In a reversible chemical reaction (where, Δx = number of moles of products-number of moles of reactants) (A) Addition of inert gas favours the forward reaction, when Δx is positive (B) Pressure has no effect on equilibrium, when Δn = ... any value of Δx (+ ve, - ve) or zero) (D) All 'a', 'b' & 'c'

Last Answer : D) All 'a', 'b' & 'c'

Which is not constant for an ideal gas? (A) (∂P/∂V)T (B) (∂V/∂T)P (C) (∂P/∂V)V (D) All (A), (B) & (C)

Description : Which is not constant for an ideal gas? (A) (∂P/∂V)T (B) (∂V/∂T)P (C) (∂P/∂V)V (D) All (A), (B) & (C)

Last Answer : (A) (∂P/∂V)T

Charles' law for gases states that (A) V/T = Constant (B) V ∝ 1/T (C) V ∝ 1/P (D) PV/T = Constant

Description : Charles' law for gases states that (A) V/T = Constant (B) V ∝ 1/T (C) V ∝ 1/P (D) PV/T = Constant

Last Answer : (A) V/T = Constant

ECE Board Exam March 1996 The standard reference antenna for the directive gain is ___________A. elementary doublet B. isotropic antenna C. half-wave dipole D. infinitesimal dipole

Description : ECE Board Exam March 1996 The standard reference antenna for the directive gain is ___________. A. elementary doublet B. isotropic antenna C. half-wave dipole D. infinitesimal dipole

Last Answer : B. isotropic antenna

The standard reference antenna forthe directive gain isthe a. infinitesimal dipole b. isotropic antenna c. elementary doublet d. half-wave dipole

Description : The standard reference antenna forthe directive gain isthe a. infinitesimal dipole b. isotropic antenna c. elementary doublet d. half-wave dipole

Last Answer : b. isotropic antenna

The volume (V) of a mass of gas varies directly as its absulute temperature (T) and iversely as the pressure (P) applied to it. The gas occupies a vol

Description : The volume (V) of a mass of gas varies directly as its absulute temperature (T) and iversely as the pressure (P) applied to it. The gas occupies a vol

Last Answer : The volume (V) of a mass of gas varies directly as its absulute temperature (T) and iversely as ... and pressure are 250 ml and 320 Pa respectively?

The volume (V) of a mass of gas varies directly as its absolute temperature (T) and inversely as the pressure (P) applied to it. The gas occupies a vo

Description : The volume (V) of a mass of gas varies directly as its absolute temperature (T) and inversely as the pressure (P) applied to it. The gas occupies a vo

Last Answer : The volume (V) of a mass of gas varies directly as its absolute temperature (T) and inversely as ... and pressure are 200 ml and 250 Pa respectively?