Q.1

For a multicomponent system, the term chemical potential is equivalent to the

  • molal concentration difference.
  • molar free energy.
  • partial molar free energy.
  • molar free energy change.
Q.2

First law of thermodynamics is mathematically stated as

  • dQ = dE + dW
  • dQ = dE - dW
  • dE = dQ + dW
  • dW = dQ + dE
Q.3

Pick out the wrong statement.

  • Surface tension of a substance vanishes at critical point, as there is no distinction between liquid and vapour phases at its critical point.
  • Entropy of a system decreases with the evolution of heat.
  • Change of internal energy is negative for exothermic reactions.
  • The accentric factor for all materials is always more than one.
Q.4

One ton of refrigeration is defined as the heat rate corresponding to melting of one ton of ice in one

  • hour
  • day
  • minute
  • second
Q.5

__________ functions are exemplified by heat and work.

  • Path
  • Point
  • State
  • none of these
Q.6

An ideal liquid refrigerant should

  • not have a subatmospheric 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.
Q.7

The compressibility factor of a gas is given by (where, V1 = actual volume of the gas V2 = gas volume predicted by ideal gas law )

  • V1/V2
  • V2/V1
  • V1-V2
  • V1.V2
Q.8

Pick out the wrong statement.

  • System (of partially miscible liquid pairs), in which the mutual solubility increases with rise in temperature, are said to possess an upper consolute temperature.
  • Systems, in which the mutual solubility increases with decrease in temperature, are said to possess lower consolute temperature.
  • Nicotine-water system shows both an upper as well as a lower consolute temperature, implying that they are partially miscible between these two limiting temperatures.
  • none of these
Q.9

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.
Q.10

The amount of heat required to decompose a compound into its elements is __________ the heat of formation of that compound from its elements.

  • less than
  • more than
  • same as
  • not related to
Q.11

The following heat engine produces power ofkW. The heat engine operates betweenK andK. It has a thermal efficiency equal toof that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is

  • 100, 000 kW
  • 160, 000 kW
  • 200, 000 kW
  • 320, 000 kW
Q.12

Vapour which is at a pressure smaller than the saturation pressure for the temperature involved is called a __________ vapour.

  • superheated
  • desuperheated
  • non-condensable
  • none of these
Q.13

Fugacity is a measure of the

  • escaping tendencies of the same substance in different phases of a system.
  • relative volatility of a mixture of two miscible liquids.
  • behaviour of ideal gases.
  • none of these.
Q.14

The quantitative effect of temperature on chemical equilibrium is given by the

  • Vant-Hoff equation.
  • Le-Chatelier's principle.
  • Arhenius equation.
  • none of these.
Q.15

What is the value of Joule-Thomson co-efficient for an ideal gas ?

  • +ve
  • -ve
  • 0
  • ∞
Q.16

A two stage compressor is used to compress an ideal gas. The gas is cooled to the initial temperature after each stage. The intermediate pressure for the minimum total work requirement should be equal to the __________ mean of P1 and P2.(where, P1 and P2 are initial and final pressures respectively)

  • logarithmic
  • arithmetic
  • geometric
  • harmonic
Q.17

Pick out the extensive property out of the following.

  • Surface tension
  • Free energy
  • Specific heat
  • Refractive index
Q.18

An irreversible process

  • is the analog of linear frictionless motion in machines.
  • is an idealised visualisation of behaviour of a system.
  • yields the maximum amount of work.
  • yields an amount of work less than that of a reversible process.
Q.19

The expression for the work done for a reversible polytropic process can be used to obtain the expression for work done for all processes, except reversible __________ process.

  • isobaric
  • isothermal
  • adiabatic
  • none of these
Q.20

Joule-Thomson co-efficient for a perfect gas is

  • zero
  • positive
  • negative
  • none of these
Q.21

Pick out the wrong statement:

  • The expansion of a gas in vacuum is an irreversible process.
  • An isometric process is a constant pressure process.
  • Entropy change for a reversible adiabatic process is zero.
  • Free energy change for a spontaneous process is negative.
Q.22

Which of the following is not affected by temperature changes ?

  • Fugacity
  • Activity co-efficient
  • Free energy
  • None of these
Q.23

A change in state involving a decrease in entropy can be spontaneous, only if

  • it is exothermic.
  • it is isenthalpic.
  • it takes place isothermally.
  • it takes place at constant volume.
Q.24

The change in Gibbs freee energy for vaporisation of a pure substance is

  • positive
  • negative
  • zero
  • may be positive or negative
Q.25

In case of a close thermodynamic system, there is __________ across the boundaries.

  • no heat and mass transfer
  • no mass transfer but heat transfer
  • mass and energy transfer
  • none of these
Q.26

If the heat of solution of an ideal gas in a liquid is negative, then its solubility at a given partial pressure varies with the temperature as

  • solubility increases as temperature increases.
  • solubility increases as temperature decreases.
  • solubility is independent of temperature.
  • solubility increases or decreases with temperature depending on the Gibbs free energy change of solution.
Q.27

If we increase the pressure on a substance (which is at its triple point), then the triple point

  • increases
  • decreases
  • remains unchanged
  • may increase or decrease ; depends on the substance
Q.28

Number of phases in a colloidal system are

  • 1
  • 2
  • 3
  • 4
Q.29

For a constant volume process

  • dE = CpdT
  • dE = CvdT
  • dQ = dE + pdV
  • dW = pdV
Q.30

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).
Q.31

At equilibrium condition, the chemical potential of a material in different phases in contact with each other is equal. The chemical potential for a real gas (μ) is given by(where, μ = standard chemical potential at unit fugacity (f° = 1 atm.) and the gas behaves ideally.)

  • μ° + RT ln f
  • μ°+ R lnf
  • μ° + T lnf
  • μ° + R/T lnf
Q.32

y = specific heat ratio of an ideal gas is equal to

  • Cp/Cv
  • Cp/(CP-R)
  • 1 + (R/CV)
  • all (a), (b) and (c)
Q.33

Joule-Thomson co-efficient depends on the

  • pressure.
  • temperature.
  • both (a) & (b).
  • neither (a) nor (b).
Q.34

With increase in compression ratio, the efficiency of the otto engine

  • increases
  • decreases
  • remains constant
  • increases linearly
Q.35

For an ideal gas, the activity co-efficient is

  • directly proportional to pressure.
  • inversely proportional to pressure.
  • unity at all pressures.
  • none of these.
Q.36

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

  • enhanced COP.
  • decreased COP.
  • no change in the value of COP.
  • increased or decreased COP ; depending upon the type of refrigerant.
Q.37

During a reversible isothermal expansion of an ideal gas, the entropy change is

  • +ve
  • 0
  • -ve
  • ∞
Q.38

In case of a reversible process (following pvn = constant), work obtained for trebling the volume (v1 = 1 m3 and v2 3 m3 ) is max imum, when the value of 'n' is

  • 0
  • 1
  • y = 1.44
  • 1.66
Q.39

Free energy changes for two reaction mechanism 'X' and 'Y are respectively -and - 5 units. It implies that X is

  • slower than Y
  • faster than Y
  • three times slower than Y
  • three times faster than Y
Q.40

The enthalpy change when ammonia gas is dissolved in water is called the heat of

  • solution
  • formation
  • dilution
  • combustion
Q.41

The kinetic energy of gas molecule is zero at

  • 0°C
  • 273°C
  • 100°C
  • -273°C
Q.42

Which law of the thermodynamics provids basis for measuring the thermodynamic property ?

  • First law
  • Zeroth law
  • Third law
  • Second law
Q.43

The chemical potential of any constituent of an ideal solution depends on the __________ of the solution.

  • temperature
  • pressure
  • composition
  • all (a), (b) and (c)
Q.44

Those solutions in which there is no volume change upon mixing the components in the liquid state and which, when diluted do not undergo any heat change (i.e. heat of dilution is zero), are called __________ solutions.

  • ideal
  • real
  • isotonic
  • none of these
Q.45

Which law of the thermodynamics provids basis for measuring the thermodynamic property ?

  • First law
  • Zeroth law
  • Third law
  • Second law
Q.46

__________ calorimeter is normally used for measuring the dryness fraction of steam, when it is very low.

  • Bucket
  • Throttling
  • Separating
  • A combination of separating & throttling
Q.47

For water at 300°C, it has a vapour pressure 8592.7 kPa and fugacity 6738.9 kPa Under these conditions, one mole of water in liquid phase has a volume of 25.cm3 and that in vapour phase in 391.1 cm3.Fugacity of water (in kPa) atkPa will be

  • 6738.9
  • 6753.5
  • 7058.3
  • 9000
Q.48

__________ functions are exemplified by heat and work.

  • Path
  • Point
  • State
  • none of these
Q.49

Those solutions in which there is no volume change upon mixing the components in the liquid state and which, when diluted do not undergo any heat change (i.e. heat of dilution is zero), are called __________ solutions.

  • ideal
  • real
  • isotonic
  • none of these
Q.50

In any spontaneous process, the __________ free energy decreases.

  • Helmholtz
  • Gibbs
  • both a & b
  • neither 'a' nor 'b'
0 h : 0 m : 1 s