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?

Question

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)

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(∂H/∂T)_P is the mathematical expression for

A. C_V

B. Entropy change

C. Gibbs free energy

D. None of these

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__________ explains the equilibrium constant for any chemical reaction.

A. Henry's law

B. Law of mass action

C. Hess's law

D. None of these

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Pick out the undesirable property for a good refrigerant.

A. High thermal conductivity

B. Low freezing point

C. Large latent heat of vaporisation

D. High viscosity

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There is a change in __________ during the phase transition.

A. Volume

B. Pressure

C. Temperature

D. All a, b & c

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Gibbs free energy of mixing at constant pressure and temperature is always

A. 0

B. ∞

C. + ve

D. - ve

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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)

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The partial pressure of each constituent present in an alloy is __________ the total vapor pressure exerted by the alloy.

A. Less than

B. Equal to

C. More than

D. Either (B) or (C); depends on the type of alloy

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Pick out the correct statement.

A. Compression ratio of an Otto engine is comparatively higher than a diesel engine

B. Efficiency of an Otto engine is higher than that of a diesel engine for the same compression ratio

C. Otto engine efficiency decreases with the rise in compression ratio, due to decrease in work produced per quantity of heat

D. Diesel engine normally operates at lower compression ratio than an Otto engine for an equal output of work

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COP of a refrigerator drawing 1 kW of power per ton of refrigeration is about

A. 0.5

B. 3.5

C. 4.5

D. 8.5

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The following heat engine produces power of 100,000 kW. The heat engine operates between 800 K and 300 K. It has a thermal efficiency equal to 50% of that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is

A. 100,000 kW

B. 160,000 kW

C. 200,000 kW

D. 320,000 kW

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A refrigerator works on the principle of __________ law of thermodynamics.

A. Zeroth

B. First

C. Second

D. Third

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__________ law of thermodynamics ascertains the direction of a particular spontaneous process.

A. Zeroth

B. First

C. Second

D. Third

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The equilibrium constant for a chemical reaction at two different temperatures is given by

A. Kp₂/Kp₁ = - (ΔH/R) (1/T₂ - 1/T₁)

B. Kp₂/Kp₁ = (ΔH/R) (1/T₂ - 1/T₁)

C. Kp₂/Kp₁ = ΔH (1/T₂ - 1/T₁)

D. Kp₂/Kp₁ = - (1/R) (1/T₂ - 1/T₁)

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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

D. Decreases logarithmically

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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

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The adiabatic throttling process of a perfect gas is one of constant enthalpy

A. In which there is a temperature drop

B. Which is exemplified by a non-steady flow expansion

C. Which can be performed in a pipe with a constriction

D. In which there is an increase in temperature

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The work done in isothermal compression compared to that in adiabatic compression will be

A. Less

B. More

C. Same

D. More or less depending upon the extent of work done

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The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances. This is the

A. Lewis-Randall rule

B. Statement of Van't Hoff Equation

C. Le-Chatelier's principle

D. None of these

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For an isothermal process, the internal energy of a gas

A. Increases

B. Decreases

C. Remains unchanged

D. Data insufficient, can't be predicted

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In the equation, PVⁿ = constant, if the value of n = 1, then it represents a reversible __________ process.

A. Isothermal

B. Isobaric

C. Polytropic

D. Adiabatic

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Pick out the wrong statement.

A. The chemical potential of a pure substance depends upon the temperature and pressure

B. The chemical potential of a component in a system is directly proportional to the escaping tendency of that component

C. The chemical potential of ith species (μ_i) in an ideal gas mixture approaches zero as the pressure or mole fraction (x_i) tends to be zero at constant temperature

D. The chemical potential of species 'i' in the mixture (μ_i) is mathematically represented as,μ_i = ∂(nG)/∂ni]_T,P,nj where, n, n_i and n_j respectively denote the total number of moles, moles of i^th species and all mole numbers except ith species. 'G' is Gibbs molar free energy

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Which of the following exemplifies an adiabatic process?

A. Melting of ice

B. Condensation of alcohol vapor

C. Sudden bursting of a cycle tube

D. Evaporation of water

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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)

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Number of components (C), phase (P) and degrees of freedom (F) are related by Gibbs phase rule as

A. P + F - C = 2

B. C = P - F + 2

C. F = C - P - 2

D. P = F - C - 2

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The Maxwell relation derived from the differential expression for the Helmholtz free energy (dA) is

A. (∂T/∂V)_S = - (∂P/∂S)_V

B. (∂S/∂P)_T = - (∂V/∂T)_P

C. (∂V/∂S)_P = (∂T/∂P)_S

D. (∂S/∂V)_T = (∂P/∂T)_V

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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

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The second law of thermodynamics states that

A. The energy change of a system undergoing any reversible process is zero

B. It is not possible to transfer heat from a lower temperature to a higher temperature

C. The total energy of system and surrounding remains the same

D. None of the above

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Entropy of the system decreases, when

A. Snow melts into water

B. A gas expands spontaneously from high pressure to low pressure

C. Water is converted into ice

D. Both (B) & (C)

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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

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Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = C_p/C_v = 7/5) and the process to be reversible, is

A. 300 × (3^2/7)

B. 300 × (3^3/5)

C. 300 × (33^3/7)

D. 300 × (3^5/7)

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Accepted Answer

C. Both (A) and (B)

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?

Correct Answer :

Show all Chemical Engineering Thermodynamics MCQ

Related Questions

(∂H/∂T)_P is the mathematical expression for

__________ explains the equilibrium constant for any chemical reaction.

Pick out the undesirable property for a good refrigerant.

There is a change in __________ during the phase transition.

Gibbs free energy of mixing at constant pressure and temperature is always

Which of the following equations is used for the prediction of activity co-efficient from experiments?

The partial pressure of each constituent present in an alloy is __________ the total vapor pressure exerted by the alloy.

Pick out the correct statement.

COP of a refrigerator drawing 1 kW of power per ton of refrigeration is about

The following heat engine produces power of 100,000 kW. The heat engine operates between 800 K and 300 K. It has a thermal efficiency equal to 50% of that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is

A refrigerator works on the principle of __________ law of thermodynamics.

__________ law of thermodynamics ascertains the direction of a particular spontaneous process.

The equilibrium constant for a chemical reaction at two different temperatures is given by

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 chemical reaction will occur spontaneously at constant pressure and temperature, if the free energy is

The adiabatic throttling process of a perfect gas is one of constant enthalpy

The work done in isothermal compression compared to that in adiabatic compression will be

The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances. This is the

For an isothermal process, the internal energy of a gas

In the equation, PVⁿ = constant, if the value of n = 1, then it represents a reversible __________ process.

Pick out the wrong statement.

Which of the following exemplifies an adiabatic process?

The equation Tds = dE - PdV applies to

Number of components (C), phase (P) and degrees of freedom (F) are related by Gibbs phase rule as

The Maxwell relation derived from the differential expression for the Helmholtz free energy (dA) is

The necessary and sufficient condition for equilibrium between two phases is

The second law of thermodynamics states that

Entropy of the system decreases, when

Specific __________ does not change during a phase change (e.g. sublimation, melting, vaporisation etc.).

Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = C_p/C_v = 7/5) and the process to be reversible, is

Also checkout

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?

Correct Answer :

Show all Chemical Engineering Thermodynamics MCQ

Related Questions

(∂H/∂T)P is the mathematical expression for

__________ explains the equilibrium constant for any chemical reaction.

Pick out the undesirable property for a good refrigerant.

There is a change in __________ during the phase transition.

Gibbs free energy of mixing at constant pressure and temperature is always

Which of the following equations is used for the prediction of activity co-efficient from experiments?

The partial pressure of each constituent present in an alloy is __________ the total vapor pressure exerted by the alloy.

Pick out the correct statement.

COP of a refrigerator drawing 1 kW of power per ton of refrigeration is about

The following heat engine produces power of 100,000 kW. The heat engine operates between 800 K and 300 K. It has a thermal efficiency equal to 50% of that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is

A refrigerator works on the principle of __________ law of thermodynamics.

__________ law of thermodynamics ascertains the direction of a particular spontaneous process.

The equilibrium constant for a chemical reaction at two different temperatures is given by

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 chemical reaction will occur spontaneously at constant pressure and temperature, if the free energy is

The adiabatic throttling process of a perfect gas is one of constant enthalpy

The work done in isothermal compression compared to that in adiabatic compression will be

The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances. This is the

For an isothermal process, the internal energy of a gas

In the equation, PVn = constant, if the value of n = 1, then it represents a reversible __________ process.

Pick out the wrong statement.

Which of the following exemplifies an adiabatic process?

The equation Tds = dE - PdV applies to

Number of components (C), phase (P) and degrees of freedom (F) are related by Gibbs phase rule as

The Maxwell relation derived from the differential expression for the Helmholtz free energy (dA) is

The necessary and sufficient condition for equilibrium between two phases is

The second law of thermodynamics states that

Entropy of the system decreases, when

Specific __________ does not change during a phase change (e.g. sublimation, melting, vaporisation etc.).

Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = Cp/Cv = 7/5) and the process to be reversible, is

Also checkout

(∂H/∂T)_P is the mathematical expression for

In the equation, PVⁿ = constant, if the value of n = 1, then it represents a reversible __________ process.

Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = C_p/C_v = 7/5) and the process to be reversible, is