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4

dW and dq are not the exact differential, because q and W are

A. State functions

B. Path functions

C. Intensive properties

D. Extensive properties

Correct Answer :

B. Path functions


Related Questions

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4

The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is

A. Less pronounced

B. More pronounced

C. Equal

D. Data insufficient, can't be predicted

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4

Gibbs-Helmholtz equation is

A. ΔF = ΔH + T [∂(ΔF)/∂T]P

B. ΔF = ΔH - TΔT

C. d(E - TS) T, V < 0

D. dP/dT = ΔHvap/T.ΔVvap

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4

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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4

A domestic refrigerator has a/an __________ cooled condenser.

A. Water

B. Air

C. Evaporative

D. Gas

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4

The value of gas constant 'R' is

A. 1.987 cal/gm mole °K

B. 1.987 BTU/lb. mole °R

C. Both (A) and (B)

D. Neither (A) nor (B)

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4

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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4

The internal energy of an ideal gas does not change in a reversible __________ process.

A. Isothermal

B. Adiabatic

C. Isobaric

D. Isometric

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4

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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4

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)

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4

Gases are cooled in Joule-Thomson expansion, when it is __________ inversion temperature.

A. Below

B. At

C. Above

D. Either 'b' or 'c'

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4

In case of a reversible process (following pvn = constant), work obtained for trebling the volume (v1 = 1 m3 and v23 m3) is maximum, when the value of 'n' is

A. 0

B. 1

C. y = 1.44

D. 1.66

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4

Minimum number of phases that exists in a system is 1. Number of chemical species in a colloidal system is

A. 1

B. 2

C. 3

D. 4

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4

A refrigerator may be termed as a

A. Heat pump

B. Heat engine

C. Carnot engine

D. None of these

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4

Which of the following is not an extensive property?

A. Free energy

B. Entropy

C. Refractive index

D. None of these

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4

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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4

The number of degrees of freedom at the triple point of water is

A. 0

B. 1

C. 2

D. 3

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4

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

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4

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

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4

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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4

Joule-Thomson co-efficient for a perfect gas is

A. Zero

B. Positive

C. Negative

D. None of these

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4

Heat requirement for decomposition of a compound into its elements is __________ that is evolved during the formation of that compound from its elements.

A. The same

B. Less than

C. Greater than

D. Different than

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4

Which of the following is not an intensive property?

A. Volume

B. Density

C. Temperature

D. Pressure

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4

Cp - Cv = R is valid for __________ gases.

A. Ideal

B. Very high pressure

C. Very low temperature

D. All of the above

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4

Which of the following units is not present in both the vapor compression refrigeration system and absorption refrigeration system?

A. Expansion valve

B. Condenser

C. Refrigerator

D. Compressor

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4

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

A. Zeroth

B. First

C. Second

D. Third

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4

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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4

For an ideal gas, the enthalpy

A. Increases with rise in pressure

B. Decreases with rise in pressure

C. Is independent of pressure

D. Is a path function

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4

Sound waves propagation in air exemplifies an __________ process.

A. Adiabatic

B. Isothermal

C. Isometric

D. None of these

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4

Pick out the wrong statement.

A. The values of (∂P/∂V)T and (∂2P/∂V2)T are zero for a real gas at its critical point

B. Heat transferred is equal to the change in the enthalpy of the system, for a constant pressure, non-flow, mechanically reversible process

C. Thermal efficiency of a Carnot engine depends upon the properties of the working fluid besides the source & sink temperatures

D. During a reversible adiabatic process, the entropy of a substance remains constant

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4

Internal energy change of a system over one complete cycle in a cyclic process is

A. Zero

B. +ve

C. -ve

D. Dependent on the path