Home

What is the correct answer?

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

Correct Answer :

B. Reversible isothermal volume change


Related Questions

What is the correct answer?

4

The heat capacities for the ideal gas state depend upon the

A. Pressure

B. Temperature

C. Both (A) & (B)

D. Neither (A) nor (B)

What is the correct answer?

4

(∂E/∂T)V is the mathematical expression for

A. CV

B. Enthalpy change

C. Free energy change

D. None of these

What is the correct answer?

4

Refrigeration cycle

A. Violates second law of thermodynamics

B. Involves transfer of heat from low temperature to high temperature

C. Both (A) and (B)

D. Neither (A) nor (B)

What is the correct answer?

4

Fugacity co-efficient of a substance is the ratio of its fugacity to

A. Mole fraction

B. Activity

C. Pressure

D. Activity co-efficient

What is the correct answer?

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

What is the correct answer?

4

An ideal liquid refrigerant should

A. Not have a sub-atmospheric vapour pressure at the temperature in the refrigerator coils

B. Not have unduly high vapour pressure at the condenser temperature

C. Both (A) and (B)

D. Have low specific heat

What is the correct answer?

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

What is the correct answer?

4

For a cyclic process, a fixed ratio between heat and work

A. Always exists

B. May exist

C. Never exists

D. Is difficult to predict

What is the correct answer?

4

Requisites of a reversible process is that the

A. System and surroundings pressure be equal

B. Friction in the system should be absent

C. System and surroundings temperature be equal

D. None of these

What is the correct answer?

4

Standard temperature and pressure (S.T.P.) is

A. 0°C and 750 mm Hg

B. 15°C and 750 mm Hg

C. 0°C and 1 kgf/cm2

D. 15°C and 1 kgf/cm2

What is the correct answer?

4

In case of an __________ process, the temperature of the system increases.

A. Isothermal compression

B. Isothermal expansion

C. Adiabatic expansion

D. Adiabatic compression

What is the correct answer?

4

For a given substance at a specified temperature, activity is __________ to fugacity.

A. Directly proportional

B. Inversely proportional

C. Equal

D. None of these

What is the correct answer?

4

Keeping the pressure constant, to double the volume of a given mass of an ideal gas at 27°C, the temperature should be raised to __________ °C.

A. 270

B. 327

C. 300

D. 540

What is the correct answer?

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

What is the correct answer?

4

In which of the following reaction equilibrium, the value of equilibrium constant Kp will be more than is Kc?

A. 2HI H2 + I2

B. N2O4 2NO2

C. 2SO2 + O2 2SO3

D. None of these

What is the correct answer?

4

Number of phases in a colloidal system is:

A. 1

B. 2

C. 3

D. 4

What is the correct answer?

4

An isentropic process is carried out at constant

A. Volume

B. Pressure

C. Temperature

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

What is the correct answer?

4

Internal energy of an ideal gas

A. Increases with increase in pressure

B. Decreases with increase in temperature

C. Is independent of temperature

D. None of these

What is the correct answer?

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

What is the correct answer?

4

Which of the following equations is used for the prediction of activity co-efficient from experiments?

A. Van Laar equation

B. Margules equation

C. Wilson's equation

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

What is the correct answer?

4

__________ increases with increase in pressure.

A. The melting point of wax

B. The boiling point of a liquid

C. Both (A) and (B)

D. Neither (A) nor (B)

What is the correct answer?

4

Which is not constant for an ideal gas?

A. (∂P/∂V)T

B. (∂V/∂T)P

C. (∂P/∂V)V

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

What is the correct answer?

4

A gas shows deviation from ideal behaviour at

A. Low pressure and high temperature

B. Low pressure and low temperature

C. Low temperature and high pressure

D. High temperature and high pressure

What is the correct answer?

4

Gibbs free energy of mixing at constant pressure and temperature is always

A. 0

B.

C. + ve

D. - ve

What is the correct answer?

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

What is the correct answer?

4

What is the number of degrees of freedom for liquid water in equilibrium with a mixture of nitrogen and water vapor?

A. 2

B. 0

C. 3

D. 1

What is the correct answer?

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)

What is the correct answer?

4

The minimum number of phases that can exist in a system is

A. 0

B. 1

C. 2

D. 3

What is the correct answer?

4

A solute distributes itself between two nonmiscible solvents in contact with each other in such a way that, at a constant temperature, the ratio of its concentrations in two layers is constant, irrespective of its total amount. This is

A. The distribution law

B. Followed from Margules equation

C. A corollary of Henry's law

D. None of these

What is the correct answer?

4

As the temperature is lowered towards the absolute zero, the value of the quantity (∂ΔF/∂T) approaches

A. Zero

B. Unity

C. Infinity

D. None of these