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Which of the following identities can be most easily used to verify steam table data for superheated steam?

A. (∂T/∂V)S = (∂p/∂S)V

B. (∂T/∂P)S = (∂V/∂S)P

C. (∂P/∂T)V = (∂S/∂V)T

D. (∂V/∂T)P = -(∂S/∂P)T

Correct Answer :

D. (∂V/∂T)P = -(∂S/∂P)T


Related Questions

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Number of degrees of freedom for a three phase system in equilibrium comprising of three nonreacting chemical species is

A. 2

B. 0

C. 1

D. 3

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4

Internal energy of an element at 1 atm and 25° C is __________ kcal/kg.mole.

A. 0

B. 273

C. 25

D. None of these

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After throttling, gas temperature

A. Decreases

B. Increases

C. Remain same

D. May increase or decrease; depends on the nature of the gas

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4

One ton of refrigeration is defined as the heat rate corresponding to melting of one ton of ice in one

A. Hour

B. Day

C. Minute

D. Second

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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

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Pick out the correct equation relating 'F' and 'A'.

A. F = A + PV

B. F = E + A

C. F = A - TS

D. F = A + TS

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If the internal energy of an ideal gas decreases by the same amount as the work done by the system, then the

A. Process must be isobaric

B. Temperature must decrease

C. Process must be adiabatic

D. Both (B) and (C)

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In a turbine, the fluid expands almost

A. Isothermally

B. Isobarically

C. Adiabatically

D. None of these

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4

Which is an example of closed system?

A. Air compressor

B. Liquid cooling system of an automobile

C. Boiler

D. None of these

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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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PVy = constant, holds good for an isentropic process, which is

A. Reversible and isothermal

B. Isothermal and irreversible

C. Reversible and adiabatic

D. Adiabatic and irreversible

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4

Lenz's law results from the law of conservation of

A. Mass

B. Momentum

C. Energy

D. None of these

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Degrees of freedom at triple point will be

A. 0

B. 1

C. 2

D. 3

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In any spontaneous process,

A. Only F decreases

B. Only A decreases

C. Both F and A decreases

D. Both F and A increase

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A two stage compressor is used to compress an ideal gas. The gas is cooled to the initial temperature after each stage. The intermediate pressure for the minimum total work requirement should be equal to the __________ mean of P1 and P2. (where, P1 and P2 are initial and final pressures respectively)

A. Logarithmic

B. Arithmetic

C. Geometric

D. Harmonic

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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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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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An isolated system can exchange __________ with its surroundings.

A. Matter

B. Energy

C. Neither matter nor energy

D. Both matter and energy

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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

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To obtain integrated form of Clausius-Clapeyron equation, ln (P2/P1) = (ΔHV/R) (1/T1 - 1/T2) from the exact Clapeyron equation, it is assumed that the

A. Volume of the liquid phase is negligible compared to that of vapour phase

B. Vapour phase behaves as an ideal gas

C. Heat of vaporisation is independent of temperature

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

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4

Which one is true for a throttling process?

A. A gas may have more than one inversion temperatures

B. The inversion temperature is different for different gases

C. The inversion temperature is same for all gases

D. The inversion temperature is the temperature at which Joule-Thomson co-efficient is infinity

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If two pure liquid constituents are mixed in any proportion to give an ideal solution, there is no change in

A. Volume

B. Enthalpy

C. Both (A) & (B)

D. Neither (A) nor (B)

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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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Trouton's ratio of __________ liquids is calculated using Kistyakowsky equation.

A. Polar

B. Non-polar

C. Both (A) & (B)

D. Neither (A) nor (B)

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4

Pick out the wrong statement.

A. The net change in entropy in any reversible cycle is always zero

B. The entropy of the system as a whole in an irreversible process increases

C. The entropy of the universe tends to a maximum

D. The entropy of a substance does not remain constant during a reversible adiabatic change

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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

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Which of the following is not correct for a reversible adiabatic process?

A. TVγ-1 = constant

B. p1-γ.TY = constant

C. PVγ = constant

D. None of these

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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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The unit of fugacity is the same as that of the

A. Pressure

B. Temperature

C. Volume

D. Molar concentration

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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