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4

On a P-V diagram of an ideal gas, suppose a reversible adiabatic line intersects a reversible isothermal line at point A. Then at a point A, the slope of the reversible adiabatic line (∂P/∂V)s and the slope of the reversible isothermal line (∂P/ ∂V)T are related as (where, y = Cp/Cv)

A. (∂P/∂V)S = (∂P/∂V)T

B. (∂P/∂V)S = [(∂P/∂V)T]Y

C. (∂P/∂V)S = y(∂P/∂V)T

D. (∂P/∂V)S = 1/y(∂P/∂V)T

Correct Answer :

C. (∂P/∂V)S = y(∂P/∂V)T


Related Questions

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4

If two gases have same reduced temperature and reduced pressure, then they will have the same

A. Volume

B. Mass

C. Critical temperature

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

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

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

A. Zeroth

B. First

C. Second

D. Third

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4

Enthalpy of a gas depends upon its

A. Temperature

B. Mass

C. Volume

D. Pressure

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4

With increase in reduced temperature, the fugacity co-efficient of a gas at constant reduced pressure

A. Increases

B. Decreases

C. Remain same

D. Decreases linearly

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4

The equation, Cp - Cv = R, is true for __________ gas.

A. No

B. Any real

C. Only ideal

D. Both (B) and (C)

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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

Equilibrium constant of a reaction varies with the

A. Initial concentration of the reactant

B. Pressure

C. Temperature

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

For a real gas, the chemical potential is given by

A. RT d ln P

B. RT d ln f

C. R d ln f

D. None of these

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4

Out of the following refrigeration cycles, which one has the minimum COP (Co-efficient of performance)?

A. Air cycle

B. Carnot cycle

C. Ordinary vapour compression cycle

D. Vapour compression with a reversible expansion engine

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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

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

Clausius-Clapeyron Equation gives accurate result, when the

A. Vapour pressure is relatively low and the temperature does not vary over wide limits

B. Vapour obeys the ideal gas law and the latent heat of vaporisation is constant

C. Volume in the liquid state is negligible compared with that in the vapour state

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

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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

Activity co-efficient is a measure of the

A. Departure from ideal solution behaviour

B. Departure of gas phase from ideal gas law

C. Vapour pressure of liquid

D. None of these

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4

Isotherm on an enthalpy-concentration diagram, for an ideal solution will be a

A. Straight line

B. Sine curve

C. Parabola

D. Hyperbola

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4

Compound having large heat of formation is

A. More stable

B. Less stable

C. Not at all stable (like nascent O2)

D. Either more or less stable; depends on the compound

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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

When a system in equilibrium is subjected to a change in temperature, pressure or concentration, the equilibrium is displaced in a direction which tends to undo the effect of the change. This is called the

A. Le-Chatelier principle

B. Kopp's rule

C. Law of corresponding state

D. Arrhenius hypothesis

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4

The melting point of paraffin wax (which contracts on solidification) __________ with pressure rise.

A. Increases

B. Decreases

C. Remains unchanged

D. Decreases linearly

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4

For an exothermic reaction

A. Only enthalpy change (ΔH) is negative

B. Only internal energy change (ΔE) is negative

C. Both ΔH and ΔE are negative

D. Enthalpy change is zero

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4

Which is a state function?

A. Specific volume

B. Work

C. Pressure

D. Temperature

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4

Which of the following is true for Virial equation of state?

A. Virial co-efficients are universal constants

B. Virial co-efficients 'B' represents three body interactions

C. Virial co-efficients are function of temperature only

D. For some gases, Virial equations and ideal gas equations are the same

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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 thermodynamic law, PVy = constant, is not applicable in case of

A. Ideal compression of air

B. Free expansion of an ideal gas

C. Adiabatic expansion of steam in a turbine

D. Adiabatic compression of a perfect gas

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4

Pick out the wrong statement.

A. Enthalpies of all elements in their standard states are assumed to be zero

B. Combustion reactions are never endothermic in nature

C. Heat of reaction at constant volume is equal to the change in internal energy

D. Clausius-Clapeyron equation is not applicable to melting process

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4

In reactions involving solids and liquids (where change in volume is negligible), the heat of reaction at constant pressure as compared to that at constant volume is

A. More

B. Less

C. Same

D. Unpredictable; depends on the particular reaction

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4

A cylinder contains 640 gm of liquid oxygen. The volume occupied (in litres) by the oxygen, when it is released and brought to standard conditions (0°C, 760 mm Hg) will be __________ litres.

A. 448

B. 224

C. 22.4

D. Data insufficient; can't be computed