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What is the correct answer?

4

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

Correct Answer :

D. (∂S/∂V)T = (∂P/∂T)V


Related Questions

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4

Pick out the correct statement.

A. Entropy and enthalpy are path functions

B. In a closed system, the energy can be exchanged with the surrounding, while matter cannot be exchanged

C. All the natural processes are reversible in nature

D. Work is a state function

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4

In polytropic process (PVn = constant), if n = 1; it means a/an __________ process.

A. Adiabatic

B. Reversible

C. Isothermal

D. None of these

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4

The chemical potential for a pure substance is __________ its partial molal free energy.

A. More than

B. Less than

C. Equal to

D. Not related to

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4

A domestic refrigerator has a/an __________ cooled condenser.

A. Water

B. Air

C. Evaporative

D. Gas

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4

Extensive properties of a thermodynamic system depend upon the __________ of the system.

A. Specific volume

B. Temperature

C. Mass

D. Pressure

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4

The value of Joule-Thomson co-efficient, in case where cooling occurs after the throttling process is

A. 0

B.

C. +ve

D. -ve

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4

In a working refrigerator, the value of COP is always

A. 0

B. < 0

C. < 1

D. > 1

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4

Air-refrigeration cycle

A. Is the most efficient of all refrigeration cycles

B. Has very low efficiency

C. Requires relatively large quantities of air to achieve a significant amount of refrigeration

D. Both (B) and (C)

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4

For the gaseous phase chemical reaction, C2H4(g) + H2O(g) ↔ C2H5OH(g), the equilibrium conversion does not depend on the

A. Steam to ethylene ratio

B. Temperature

C. Pressure

D. None of these

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4

Which of the following is not affected by temperature changes?

A. Fugacity

B. Activity co-efficient

C. Free energy

D. None of these

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4

Domestic refrigerator usually works on the __________ refrigeration cycle.

A. Carnot

B. Air

C. Absorption

D. vapour-ejection

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4

Mollier chart is a __________ plot.

A. Pressure vs. enthalpy

B. Pressure vs. volume

C. Enthalpy vs. entropy

D. Temperature vs. entropy

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4

Gibbs phase rule finds application, when heat transfer occurs by

A. Conduction

B. Convection

C. Radiation

D. Condensation

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4

During adiabatic expansion of gas

A. Pressure remains constant

B. Pressure is increased

C. Temperature remains constant

D. None of these

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4

The main feature of Carnot refrigeration cycle is that, it

A. Does not need the addition of external work for its functioning

B. Transfers heat from high temperature to low temperature

C. Accomplishes the reverse effect of the heat engine

D. None of these

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4

Standard temperature and pressure (S.T.P.) is

A. 0°C and 750 mm Hg

B. 15°C and 750 mm Hg

C. 0°C and 1 kgf/cm2

D. 15°C and 1 kgf/cm2

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4

There is a change in __________ during the phase transition.

A. Volume

B. Pressure

C. Temperature

D. All a, b & c

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4

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

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4

Entropy of an ideal gas depends upon its

A. Pressure

B. Temperature

C. Both (A) & (B)

D. Neither (A) nor (B)

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4

A closed system is cooled reversibly from 100°C to 50°C. If no work is done on the system

A. its internal energy (U) decreases and its entropy (S) increases

B. U and S both decreases

C. U decreases but S is constant

D. U is constant but S decreases

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4

A gas can be liquefied by pressure alone only, when its temperature is __________ its critical temperature.

A. Less than

B. More than

C. Equal to or higher than

D. Less than or equal to

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4

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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4

The amount of heat required to decompose a compound into its elements is __________ the heat of formation of that compound from its elements.

A. Less than

B. More than

C. Same as

D. Not related to

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4

During a reversible isothermal expansion of an ideal gas, the entropy change is

A. +ve

B. 0

C. -ve

D.

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4

What happens in a reversible adiabatic expansion process?

A. Heating takes place

B. Cooling takes place

C. Pressure is constant

D. Temperature is constant

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4

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

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4

Pick out the wrong statement.

A. Minimum number of degree of freedom of a system is zero

B. Degree of freedom of a system containing a gaseous mixture of helium, carbon dioxide and hydrogen is 4

C. For a two phase system in equilibrium made up of four non-reacting chemical species, the number of degrees of freedom is 4

D. Enthalpy and internal energy change is zero during phase change processes like melting, vaporisation and sublimation

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4

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

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4

Entropy is a/an

A. State function

B. Macroscopic property

C. Extensive property

D. None of these

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4

In the decomposition of PCl5 represented by, PCl5 PCl3 + Cl2, decrease in the pressure of the system will __________ the degree of dissociation of PCl5.

A. Increase

B. Decrease

C. Not alter

D. None of these