4

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

Expansion of a real gas

Reversible isothermal volume change

Heating of an ideal gas

Cooling of a real gas

B. Reversible isothermal volume change

4

# The heat capacities for the ideal gas state depend upon the

Pressure

Temperature

Both (A) & (B)

Neither (A) nor (B)

4

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

CV

Enthalpy change

Free energy change

None of these

4

# Refrigeration cycle

Violates second law of thermodynamics

Involves transfer of heat from low temperature to high temperature

Both (A) and (B)

Neither (A) nor (B)

4

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

Mole fraction

Activity

Pressure

Activity co-efficient

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

5.2

6.2

0.168

Data insufficient, can't be found out

4

# An ideal liquid refrigerant should

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

Not have unduly high vapour pressure at the condenser temperature

Both (A) and (B)

Have low specific heat

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)

(∂P/∂V)S = (∂P/∂V)T

(∂P/∂V)S = [(∂P/∂V)T]Y

(∂P/∂V)S = y(∂P/∂V)T

(∂P/∂V)S = 1/y(∂P/∂V)T

4

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

Always exists

May exist

Never exists

Is difficult to predict

4

# Requisites of a reversible process is that the

System and surroundings pressure be equal

Friction in the system should be absent

System and surroundings temperature be equal

None of these

4

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

0°C and 750 mm Hg

15°C and 750 mm Hg

0°C and 1 kgf/cm2

15°C and 1 kgf/cm2

4

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

Isothermal compression

Isothermal expansion

4

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

Directly proportional

Inversely proportional

Equal

None of these

4

270

327

300

540

4

# Cv for an ideal gas

Does not depend upon temperature

Is independent of pressure only

Is independent of volume only

Is independent of both pressure and volume

4

2HI H2 + I2

N2O4 2NO2

2SO2 + O2 2SO3

None of these

4

1

2

3

4

4

# An isentropic process is carried out at constant

Volume

Pressure

Temperature

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

4

# Internal energy of an ideal gas

Increases with increase in pressure

Decreases with increase in temperature

Is independent of temperature

None of these

4

4 J

0

8 J

4

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

Van Laar equation

Margules equation

Wilson's equation

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

4

# __________ increases with increase in pressure.

The melting point of wax

The boiling point of a liquid

Both (A) and (B)

Neither (A) nor (B)

4

# Which is not constant for an ideal gas?

(∂P/∂V)T

(∂V/∂T)P

(∂P/∂V)V

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

4

# A gas shows deviation from ideal behaviour at

Low pressure and high temperature

Low pressure and low temperature

Low temperature and high pressure

High temperature and high pressure

4

0

+ ve

- ve

4

# Which of the following represents the Virial equation of state?

T = [RT/(V- b)] - [a/√T. V(V + b)]

PV/RT = 1 + (B/V) + (C/V2) + ……

n1u2 + μ2μ1 = 0

None of these

4

2

0

3

1

4

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

Critical temperature

Melting point

Freezing point

Both (B) and (C)

4

0

1

2

3

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

The distribution law

Followed from Margules equation

A corollary of Henry's law

None of these