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4

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

Correct Answer :

A. Temperature


Related Questions

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4

The total change in the enthalpy of a system is independent of the

A. Number of intermediate chemical reactions involved

B. Pressure and temperature

C. State of combination and aggregation in the beginning and at the end of the reaction

D. None of these

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4

Solid and liquid phases of a substance are in equilibrium at the

A. Critical temperature

B. Melting point

C. Freezing point

D. Both (B) and (C)

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4

Which of the following represents the Virial equation of state?

A. T = [RT/(V- b)] - [a/√T. V(V + b)]

B. PV/RT = 1 + (B/V) + (C/V2) + ……

C. n1u2 + μ2μ1 = 0

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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4

Chemical potential of ith component of a system is given by

A. μi = (∂F/∂ni)T, P, ni

B. μi = (∂A/∂ni)T, P, ni

C. μi = (∂F/∂ni)T, P

D. μi = (∂A/∂ni)T, P

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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

Cv is given by

A. (∂E/∂T)V

B. (∂E/∂V)T

C. (∂E/∂P)V

D. (∂V/∂T)P

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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

Which of the following is a thermodynamic property of a system?

A. Concentration

B. Mass

C. Temperature

D. Entropy

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4

Entropy change in case of reversible adiabatic process is

A. Minimum

B. Zero

C. Maximum

D. Indeterminate

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4

At 60° C, vapour pressure of methanol and water are 84.562 kPa and 19.953 kPa respectively. An aqueous solution of methanol at 60° C exerts a pressure of 39.223 kPa; the liquid phase and vapour phase mole fractions of methanol are 0.1686 and 0.5714 respectively. Activity co-efficient of methanol is

A. 1.572

B. 1.9398

C. 3.389

D. 4.238

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4

Ideal gas law is applicable at

A. Low T, low P

B. High T, high P

C. Low T, high P

D. High T, low P

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4

The expression, nRT ln(P1/P2), is for the __________of an ideal gas.

A. Compressibility

B. Work done under adiabatic condition

C. Work done under isothermal condition

D. Co-efficient of thermal expansion

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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 ammonia synthesis reaction represented by N2 + 3H2 2NH3; ΔH = - 22.4 kcal, is

A. Endothermic

B. Exothermic

C. Isothermal

D. Adiabatic

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4

For a constant volume process __________ by the system is used only to increase the internal energy.

A. Heat absorbed

B. Work done

C. Both (A) & (B)

D. Neither (A) nor (B)

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4

Translational kinetic energy of molecules of an ideal gas is proportional to (where, T = absolute temperature of the gas)

A. T

B. √T

C. T2

D. 1/√T

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4

In vapour compression refrigeration system, if the evaporator temperature and the condenser temperatures are -13°C and 37°C respectively, the Carnot COP will be

A. 5.2

B. 6.2

C. 0.168

D. Data insufficient, can't be found out

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4

What is the number of degree of freedom for a system of two miscible non-reacting species in vapor-liquid equilibrium forming an azeotrope?

A. 0

B. 2

C. 1

D. 3

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4

For water at 300°C, it has a vapour pressure 8592.7 kPa and fugacity 6738.9 kPa Under these conditions, one mole of water in liquid phase has a volume of 25.28 cm3 and that in vapour phase in 391.1 cm3.Fugacity of water (in kPa) at 9000 kPa will be

A. 6738.9

B. 6753.5

C. 7058.3

D. 9000

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4

Pressure-enthalpy chart is useful in refrigeration. The change in internal energy of an ideal fluid used in ideal refrigeration cycle is

A. Positive

B. Negative

C. Zero

D. Infinity

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4

A gas has a volume of 27.3 c.c. at 0°C. Its volume at 10°C (if pressure remains unchanged) will be __________ c.c.

A. 2.73

B. 28.3

C. 273

D. 283

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4

Mollier diagram is a plot of

A. Temperature vs. enthalpy

B. Temperature vs. enthalpy

C. Entropy vs. enthalpy

D. Temperature vs. internal energy

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4

Which of the following has the minimum value of COP for a given refrigeration effect?

A. Reverse Carnot cycle

B. Ordinary vapour-compression cycle

C. Vapour-compression process with a reversible expansion engine

D. Air refrigeration cycle

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4

The expression for entropy change given by, ΔS = nR ln (V2/V1) + nCv ln (T2/T1) is valid for

A. Reversible isothermal volume change

B. Heating of a substance

C. Cooling of a substance

D. Simultaneous heating and expansion of an ideal gas

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4

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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4

Pick out the wrong statement.

A. Cp of monatomic gases such as metallic vapor is about 5 kcal/kg.atom

B. The heat capacity of solid inorganic substance is exactly equal to the heat capacity of the substance in the molten state

C. There is an increase in entropy, when a spontaneous change occurs in an isolated system

D. At absolute zero temperature, the heat capacity for many pure crystalline substances is zero

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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

Law of corresponding states says that

A. Two different gases behave similarly, if their reduced properties (i.e. P, V and T) are same

B. The surface of separation (i. e. the meniscus) between liquid and vapour phase disappears at the critical temperature

C. No gas can be liquefied above the critical temperature, howsoever high the pressure may be.

D. The molar heat of energy of gas at constant volume should be nearly constant (about 3 calories)

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4

A gas mixture of three components is brought in contact with a dispersion of an organic phase in water. The degree of freedom of the system is

A. 3

B. 4

C. 5

D. 6