Helmholtz free energy (A) is defined as

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Helmholtz free energy (A) is defined as

A. A = H - TS

B. A = E - TS

C. A = H + TS

D. None of these

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__________ decreases during adiabatic throttling of a perfect gas.

A. Entropy

B. Temperature

C. Enthalpy

D. Pressure

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A large iceberg melts at the base, but not at the top, because of the reason that

A. Ice at the base contains impurities which lowers its melting point

B. Due to the high pressure at the base, its melting point reduces

C. The iceberg remains in a warmer condition at the base

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

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For a given substance at a specified temperature, activity is __________ to fugacity.

A. Directly proportional

B. Inversely proportional

C. Equal

D. None of these

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Tea kept in a thermos flask is vigorously shaken. If the tea is considered as a system, then its temperature will

A. Increase

B. Decrease

C. Remain unchanged

D. First fall and then rise

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For a multi-component system, the term chemical potential is equivalent to the

A. Molal concentration difference

B. Molar free energy

C. Partial molar free energy

D. Molar free energy change

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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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During Joule-Thomson expansion of gases

A. Enthalpy remains constant

B. Entropy remains constant

C. Temperature remains constant

D. None of these

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A reasonably general expression for vapourliquid phase equilibrium at low to moderate pressure is φ_i y_i P = Y_i x_if_i° where, Φ is a vapor fugacity component, Y_i is the liquid activity co-efficient and f_i° is the fugacity of the pure component i. the K_i value (Y_i = K_i x_i) is therefore, in general a function of

A. Temperature only

B. Temperature and pressure only

C. Temperature, pressure and liquid composition x_i only

D. Temperature, pressure, liquid composition x_i and vapour composition yi

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The expression for entropy change, ΔS = n C_p . ln (T₂/T₁), is valid for the __________ of a substance.

A. Simultaneous pressure & temperature change

B. Heating

C. Cooling

D. Both (B) and (C)

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Van Laar equation deals with the activity coefficients in

A. Binary solutions

B. Ternary solutions

C. Azeotropic mixture only

D. None of these

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The work done in an adiabatic change in a particular gas depends upon changes in the __________ only.

A. Temperature

B. Specific heat

C. Volume

D. Pressure

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__________ 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)

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The temperature at the eutectic point of the system is the __________ temperature that can be attained in the system.

A. Lowest

B. Highest

C. Average

D. None of these

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While dissolving a gas into a liquid at a constant temperature, the ratio of the concentration of the gas in the solution phase and in the gaseous phase is

A. Infinity

B. Unity

C. Constant

D. Negative

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A thermodynamic system is taken from state A to B along ACB and is brought back to A along BDA as shown below in the P-V diagram. The net work done during the complete cycle is given by the area covered by

A. P₁ACBP₂P₁

B. ACBB¹A¹A

C. ACBDA

D. ADBB¹A¹A

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For a real gas, the chemical potential is given by

A. RT d ln P

B. RT d ln f

C. R d ln f

D. None of these

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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

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Enthalpy changes over a constant pressure path are always zero for __________ gas.

A. Any

B. A perfect

C. An easily liquefiable

D. A real

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If the molar heat capacities (C_p or C_v) of the reactants and products of a chemical reaction are identical, then, with the increase in temperature, the heat of reaction will

A. Increase

B. Decrease

C. Remain unaltered

D. Increase or decrease; depends on the particular reaction

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High __________ is an undesirable property for a good refrigerant.

A. Specific heat

B. Latent heat of vaporisation

C. Viscosity

D. Specific vapor volume

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At the critical point of a substance

A. The surface tension vanishes

B. Liquid and vapour have the same density

C. There is no distinction between liquid and vapour phases

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

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Claude gas liquefaction process employs cooling

A. At constant pressure

B. By throttling

C. By expansion in an engine

D. None of these

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Which of the following is not an intensive property?

A. Volume

B. Density

C. Temperature

D. Pressure

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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

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The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be

A. More

B. Less

C. Same

D. Data insufficient to predict

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Measurement of thermodynamic property of temperature is facilitated by __________ law of thermodynamics.

A. 1st

B. Zeroth

C. 3rd

D. None of these

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Throttling process is a/an __________ process.

A. Reversible and isothermal

B. Irreversible and constant enthalpy

C. Reversible and constant entropy

D. Reversible and constant enthalpy

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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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What is the value of maximum COP in case of absorption refrigeration, if refrigeration provided is at temperature, T_R (where, T₁ and T₂ are source & surrounding temperatures respectively.)?

A. T_R/(T₂ - T_R) × (T₁ - T₂)/T₁

B. T_R/(T₂ - T_R) × T₁/(T₁ - T₂)

C. T_R/(T₁ - T_R) × (T₁ - T₂)/T₁

D. None of these

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Dry ice is

A. Moisture free ice

B. Solid helium

C. Solid carbon dioxide

D. None of these

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Accepted Answer

B. A = E - TS

Helmholtz free energy (A) is defined as

Correct Answer :

Show all Chemical Engineering Thermodynamics MCQ

Related Questions

__________ decreases during adiabatic throttling of a perfect gas.

A large iceberg melts at the base, but not at the top, because of the reason that

For a given substance at a specified temperature, activity is __________ to fugacity.

Tea kept in a thermos flask is vigorously shaken. If the tea is considered as a system, then its temperature will

For a multi-component system, the term chemical potential is equivalent to the

The equation Tds = dE - PdV applies to

During Joule-Thomson expansion of gases

The expression for entropy change, ΔS = n C_p . ln (T₂/T₁), is valid for the __________ of a substance.

Van Laar equation deals with the activity coefficients in

The work done in an adiabatic change in a particular gas depends upon changes in the __________ only.

__________ does not change during phase transformation processes like sublimation, melting & vaporisation.

The temperature at the eutectic point of the system is the __________ temperature that can be attained in the system.

While dissolving a gas into a liquid at a constant temperature, the ratio of the concentration of the gas in the solution phase and in the gaseous phase is

A thermodynamic system is taken from state A to B along ACB and is brought back to A along BDA as shown below in the P-V diagram. The net work done during the complete cycle is given by the area covered by

For a real gas, the chemical potential is given by

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:

Enthalpy changes over a constant pressure path are always zero for __________ gas.

If the molar heat capacities (C_p or C_v) of the reactants and products of a chemical reaction are identical, then, with the increase in temperature, the heat of reaction will

High __________ is an undesirable property for a good refrigerant.

At the critical point of a substance

Claude gas liquefaction process employs cooling

Which of the following is not an intensive property?

The equation DU = Tds - PdV is applicable to infinitesimal changes occuring in

The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be

Measurement of thermodynamic property of temperature is facilitated by __________ law of thermodynamics.

Throttling process is a/an __________ process.

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

What is the value of maximum COP in case of absorption refrigeration, if refrigeration provided is at temperature, T_R (where, T₁ and T₂ are source & surrounding temperatures respectively.)?

Dry ice is

Also checkout

Helmholtz free energy (A) is defined as

Correct Answer :

Show all Chemical Engineering Thermodynamics MCQ

Related Questions

__________ decreases during adiabatic throttling of a perfect gas.

A large iceberg melts at the base, but not at the top, because of the reason that

For a given substance at a specified temperature, activity is __________ to fugacity.

Tea kept in a thermos flask is vigorously shaken. If the tea is considered as a system, then its temperature will

For a multi-component system, the term chemical potential is equivalent to the

The equation Tds = dE - PdV applies to

During Joule-Thomson expansion of gases

The expression for entropy change, ΔS = n Cp . ln (T2/T1), is valid for the __________ of a substance.

Van Laar equation deals with the activity coefficients in

The work done in an adiabatic change in a particular gas depends upon changes in the __________ only.

__________ does not change during phase transformation processes like sublimation, melting & vaporisation.

The temperature at the eutectic point of the system is the __________ temperature that can be attained in the system.

While dissolving a gas into a liquid at a constant temperature, the ratio of the concentration of the gas in the solution phase and in the gaseous phase is

A thermodynamic system is taken from state A to B along ACB and is brought back to A along BDA as shown below in the P-V diagram. The net work done during the complete cycle is given by the area covered by

For a real gas, the chemical potential is given by

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:

Enthalpy changes over a constant pressure path are always zero for __________ gas.

If the molar heat capacities (Cp or Cv) of the reactants and products of a chemical reaction are identical, then, with the increase in temperature, the heat of reaction will

High __________ is an undesirable property for a good refrigerant.

At the critical point of a substance

Claude gas liquefaction process employs cooling

Which of the following is not an intensive property?

The equation DU = Tds - PdV is applicable to infinitesimal changes occuring in

The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be

Measurement of thermodynamic property of temperature is facilitated by __________ law of thermodynamics.

Throttling process is a/an __________ process.

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

What is the value of maximum COP in case of absorption refrigeration, if refrigeration provided is at temperature, TR (where, T1 and T2 are source & surrounding temperatures respectively.)?

Dry ice is

Also checkout

The expression for entropy change, ΔS = n C_p . ln (T₂/T₁), is valid for the __________ of a substance.

If the molar heat capacities (C_p or C_v) of the reactants and products of a chemical reaction are identical, then, with the increase in temperature, the heat of reaction will

What is the value of maximum COP in case of absorption refrigeration, if refrigeration provided is at temperature, T_R (where, T₁ and T₂ are source & surrounding temperatures respectively.)?