4

-273

0

-78

5

C. -78

4

# Equation which relates pressure, volume and temperature of a gas is called the

Equation of state

Gibbs Duhem equation

Ideal gas equation

None of these

4

Zero

Negative

More than zero

Indeterminate

4

Zeroth

First

Second

Third

4

ds = 0

ds <0

ds > 0

ds = Constant

4

# Second law of thermodynamics is concerned with the

Amount of energy transferred

Direction of energy transfer

Irreversible processes only

Non-cyclic processes only

4

# Pick out the wrong statement.

Minimum number of degree of freedom of a system is zero

Degree of freedom of a system containing a gaseous mixture of helium, carbon dioxide and hydrogen is 4

For a two phase system in equilibrium made up of four non-reacting chemical species, the number of degrees of freedom is 4

Enthalpy and internal energy change is zero during phase change processes like melting, vaporisation and sublimation

4

# As the entropy of the universe is increasing, day by day, the work producing capacity of a heat engine is

Not changed

Decreasing

Increasing

Data sufficient, can't be predicted

4

# Adiabatic compression of a saturated water vapour makes it

Supersaturated

Superheated

Both (A) and (B)

Neither (A) nor (B)

4

Zero

Unity

Infinity

None of these

4

# A refrigeration cycle is the same as a __________ cycle,

Turbine

Heat engine

Reversed heat engine

None of these

4

# High pressure steam is expanded adiabatically and reversibly through a well insulated turbine, which produces some shaft work. If the enthalpy change and entropy change across the turbine are represented by ΔH and ΔS respectively for this process:

Δ H = 0 and ΔS = 0

Δ H ≠ 0 and ΔS = 0

Δ H ≠ 0 and ΔS ≠ 0

Δ H = 0 and ΔS ≠ 0

4

# For multi-component multiple phases to be in equilibrium at the same pressure and temperature, the __________ of each component must be same in all phases.

Chemical potential

Fugacity

Both (A) and (B)

Neither (A) nor (B)

4

Equilibrium

4

# A reasonably general expression for vapourliquid phase equilibrium at low to moderate pressure is φi yi P = Yi xifi° where, Φ is a vapor fugacity component, Yi is the liquid activity co-efficient and fi° is the fugacity of the pure component i. the Ki value (Yi = Ki xi) is therefore, in general a function of

Temperature only

Temperature and pressure only

Temperature, pressure and liquid composition xi only

Temperature, pressure, liquid composition xi and vapour composition yi

4

2HI H2 + I2

N2O4 2NO2

2SO2 + O2 2SO3

None of these

4

# During Joule-Thomson expansion of gases

Enthalpy remains constant

Entropy remains constant

Temperature remains constant

None of these

4

Cv.dT

Cp.dT

∫ Cp.dT

∫ Cv.dT

4

# Pick out the correct statement.

Entropy and enthalpy are path functions

In a closed system, the energy can be exchanged with the surrounding, while matter cannot be exchanged

All the natural processes are reversible in nature

Work is a state function

4

# Which of the following decreases with increase in pressure?

Melting point of ice

Melting point of wax

Boiling point of liquids

None of these

4

# Which of the following is not affected by temperature changes?

Fugacity

Activity co-efficient

Free energy

None of these

4

Zeroth

First

Second

Third

4

# Reduced pressure of a gas is the ratio of its

Pressure to critical pressure

Critical pressure to pressure

Pressure to pseudocritical pressure

Pseudocritical pressure to pressure

4

# When pressure is applied on the system, ice ↔ water, then

Equilibrium cannot be established

More ice will be formed

More water will be formed

Evaporation of water will take place

4

Isothermal

Isobaric

Isometric

4

# At the critical point of a substance

The surface tension vanishes

Liquid and vapour have the same density

There is no distinction between liquid and vapour phases

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

4

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

Number of intermediate chemical reactions involved

Pressure and temperature

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

None of these

4

# Which of the following is not correct for a reversible adiabatic process?

TVγ-1 = constant

p1-γ.TY = constant

PVγ = constant

None of these

4

λb/Tb

Tb/λb

√(λb/Tb)

√(Tb/λb)

4

# Maxwell's relation corresponding to the identity, dH = dS = Vdp + Σμi dni is

(∂T/∂V)S, ni = -(∂P/∂S)V, ni

(∂S/∂P)T, ni = (∂V/∂T)P, ni

(∂S/∂V)T, ni = (∂P/∂T)V, ni

(∂T/∂P)S, ni = (∂V/∂S)P, ni