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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

Correct Answer :

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


Related Questions

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4

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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4

For spontaneous changes in an isolated system (S = entropy)

A. ds = 0

B. ds <0

C. ds > 0

D. ds = Constant

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4

The unity of Planck's constant 'h' in the equation, E = hv is

A. J/s

B. J.S

C. J/kmol

D. kmol/J

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4

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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4

Melting of ice is an example of an __________ process.

A. Adiabatic

B. Isothermal

C. Isometric

D. None of these

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4

Melting of ice exemplifies a/an

A. Adiabatic process

B. Endothermic reaction

C. Exothermic reaction

D. Process involving a chemical reaction

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4

The standard state of a gas (at a given temperature) is the state in which fugacity is equal to

A. Unity

B. Activity

C. Both (A) & (B)

D. Neither (A) nor (B)

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4

The temperature at which a real gas obeys the ideal gas laws over a wide range of pressure is called the __________ temperature.

A. Critical

B. Boyle

C. Inversion

D. Reduced

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4

Which of the following is not a reversible process?

A. Expansion of an ideal gas against constant pressure

B. Atmospheric pressure vaporisation of water at 100°C

C. Solution of NaCl in water at 50°C

D. None of these

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4

Isobaric process means a constant process.

A. Temperature

B. Pressure

C. Volume

D. Entropy

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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

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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4

The expression for entropy change given by, ΔS = - nR ln (P2/P1), holds good for

A. Expansion of a real gas

B. Reversible isothermal volume change

C. Heating of an ideal gas

D. Cooling of a real gas

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4

Pick out the extensive property out of the following.

A. Surface tension

B. Free energy

C. Specific heat

D. Refractive index

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4

In jet refrigerators, the refrigerating fluid is practically always

A. Water

B. Ammonia

C. Freon

D. Brine

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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

Which is a state function?

A. Specific volume

B. Work

C. Pressure

D. Temperature

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4

The difference between isothermal compressibility and adiabatic compressibility for an ideal gas is

A. 0

B. +ve

C. -ve

D.

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4

Which of the following decreases with increase in pressure?

A. Melting point of ice

B. Melting point of wax

C. Boiling point of liquids

D. None of these

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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

In a P-V diagram (for an ideal gas), an isothermal curve will coincide within adiabatic curve (through a point), when

A. Cp < Cv

B. Cp = Cv

C. Cp > Cv

D. C ≥ Cv

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4

Pick out the wrong statement:

A. The expansion of a gas in vacuum is an irreversible process

B. An isometric process is a constant pressure process

C. Entropy change for a reversible adiabatic process is zero

D. Free energy change for a spontaneous process is negative

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4

The expression, nCv(T2 - T1), is for the __________ of an ideal gas.

A. Work done under adiabatic condition

B. Co-efficient of thermal expansion

C. Compressibility

D. None of these

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4

The extensive properties are

A. Volume, mass and number of moles

B. Free energy, entropy and enthalpy

C. Both (A) and (B)

D. None of these

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4

What is the degree of freedom for a system comprising liquid water equilibrium with its vapour?

A. 0

B. 1

C. 2

D. 3

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4

An isentropic process is carried out at constant

A. Volume

B. Pressure

C. Temperature

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

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4

Isentropic process means a constant __________ process.

A. Enthalpy

B. Pressure

C. Entropy

D. None of these

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4

Pick out the correct statement.

A. If an insoluble gas is passed through a volatile liquid placed in a perfectly insulated container, the temperature of the liquid will increase

B. A process is irreversible as long as Δ S for the system is greater than zero

C. The mechanical work done by a system is always equal to∫P.dV

D. The heat of formation of a compound is defined as the heat of reaction leading to the formation of the compound from its reactants

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4

In case of vapour compression refrigeration system, elevating the evaporator temperature (keeping the condenser temperature constant) results in

A. Enhanced COP

B. Decreased COP

C. No change in the value of COP

D. Increased or decreased COP; depending upon the type of refrigerant

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4

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

A. 300 × (32/7)

B. 300 × (33/5)

C. 300 × (333/7)

D. 300 × (35/7)