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What is the correct answer?

4

With increase in pressure (above atmospheric pressure), the Cp of a gas

A. Increases

B. Decreases

C. Remains unchanged

D. First decreases and then increases

Correct Answer :

A. Increases


Related Questions

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4

Cv for an ideal gas

A. Does not depend upon temperature

B. Is independent of pressure only

C. Is independent of volume only

D. Is independent of both pressure and volume

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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

4 kg moles of an ideal gas expands in vacuum spontaneously. The work done is

A. 4 J

B.

C. 0

D. 8 J

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4

Water on heating from 1 to 4°C

A. Contracts

B. Expands

C. Has same volume

D. May contract or expand

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4

When liquid and vapour phases of one component system are in equilibrium (at a given temperature and pressure), the molar free energy is

A. More in vapour phase

B. More in liquid phase

C. Same in both the phases

D. Replaced by chemical potential which is more in vapour phase

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4

The most important application of distribution law is in

A. Evaporation

B. Liquid extraction

C. Drying

D. Distillation

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4

For an isothermal reversible compression of an ideal gas

A. Only ΔE = 0

B. Only ΔH =0

C. ΔE = ΔH = 0

D. dQ = dE

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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

The equation, PV = nRT, is best obeyed by gases at

A. Low pressure & high temperature

B. High pressure & low temperature

C. Low pressure & low temperature

D. None of these

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4

The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be

A. More

B. Less

C. Same

D. Data insufficient to predict

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4

The first law of thermodynamics is a restatement of the law of conservation of

A. Mass

B. Energy

C. Momentum

D. None of these

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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

Efficiency of a Carnot engine working between temperatures T1 and T2 (T1 < T) is

A. (T2 - T1)/T2

B. (T2 - T1)/T1

C. (T1 - T2)/T2

D. (T1 - T2)/T1

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4

Entropy, which is a measure of the disorder of a system, is:

A. Independent of pressure

B. Independent of temperature

C. Zero at absolute zero temperature for a perfect crystalline substance

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

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4

What is the value of maximum COP in case of absorption refrigeration, if refrigeration provided is at temperature, TR (where, T1 and T2 are source & surrounding temperatures respectively.)?

A. TR/(T2 - TR) × (T1 - T2)/T1

B. TR/(T2 - TR) × T1/(T1 - T2)

C. TR/(T1 - TR) × (T1 - T2)/T1

D. None of these

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4

In the reaction, C + O2 → CO2; ΔH = - 94 kcal. What is the heat content (enthalpy) of O2?

A. -94 kcal

B. > -94 kcal

C. < - 94 kcal

D. Zero

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4

A Carnot cycle consists of the following steps:

A. Two isothermal and two isentropic

B. Two isobaric and two isothermal

C. Two isochoric and two isobaric

D. Two isothermals and two isochoric

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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

Pick out the wrong statement pertaining to the decomposition of PCl5 represented by, PCl5 PCl3 + Cl2.Degree of dissociation of PCl5 will

A. Decrease on addition of Cl2

B. Increase on addition of an inert gas at constant pressure

C. Decrease on increasing the pressure of the system

D. None of these

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4

The following heat engine produces power of 100,000 kW. The heat engine operates between 800 K and 300 K. It has a thermal efficiency equal to 50% of that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is

A. 100,000 kW

B. 160,000 kW

C. 200,000 kW

D. 320,000 kW

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4

Heat pump

A. Accomplishes only space heating in winter

B. Accomplishes only space cooling in summer

C. Accomplishes both (A) and (B)

D. Works on Carnot cycle

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4

Work done is a

A. Property of the system

B. Path function

C. Point function

D. State description of a system

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4

In case of the decomposition of hydroiodic acid (2HI H2 + I2), addition of H2 (at equilibrium condition) will

A. Increase the partial pressure of I2

B. Decrease the partial pressure of HI

C. Diminish the degree of dissociation of HI

D. None of these

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4

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

A. Increased COP

B. Same COP

C. Decreased COP

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

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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

Maximum work that could be secured by expanding the gas over a given pressure range is the __________ work.

A. Isothermal

B. Adiabatic

C. Isentropic

D. None of these

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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

Entropy is a/an

A. State function

B. Macroscopic property

C. Extensive property

D. None of these

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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

The co-efficient of performance (COP) of a refrigerating system, which is its index of performance, is defined as the ratio of useful refrigeration to the net work. The units of __________ and COP are the same.

A. Kinematic viscosity

B. Work

C. Temperature

D. None of these