Thermodynamics Part 3 Flashcards by Chris Wilfred Estrada

Entropy is a/an
state function
macroscopic property
extensive property
none of these

none of these

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At triple point (for one component system), vapour pressure of solid as compared to that of liquid will be
more
less
same
more or less ; depending on the system.

same

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4 kg moles of an ideal gas expands in vacuum spontaneously. The work done is
4 J
infinity
0
8 J

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Which of the following is not correct for a reversible adiabatic process ?
TVγ-1 = constant
p1-γ.TY = constant
PVγ = constant
none of these

none of these

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The efficiency of a Carnot heat engine operating between absolute temperatures T1 and T2 (when, T1 > T2) is given by (T1 - T2)/T1. The co-efficient of performance (C.O.P.) of a Carnot heat pump operating between T1 and T2 is given by
T1/(T1-T2)
T2/(T1-T2)
T1/T2
T2/R1

T1/(T1-T2)

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Throttling (Joule-Thomson effect) process is a constant __________ process.
enthalpy
entropy
pressure
none of these

enthalpy

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Boiling of liquid is accompanied with increase in the
vapor pressure.
specific Gibbs free energy.
specific entropy.
all of these

vapor pressure.

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Change of state namely evaportation condensation, freezing and melting is an __________ process.
isothermal
adiabatic
isobaric
isochoric

isothermal

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Which of the following is not an equation of state?
Bertholet equation
Clausius Clayperon equation
Beattie-Bridgeman equation
None of these

Clausius Clayperon equation

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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.

low temperature and high pressure.

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The difference between isothermal compressibility and adiabatic compressibility for an ideal gas is
0
+ve
-ve
infinity

+ve

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The expression for entropy change given by, delta-S = - 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.

reversible isothermal volume change.

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With increase in temperature, the internal energy of a substance
increases
decreases
remains unchanged
may increase or decrease; depends on the substance

increases

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It is desired to bring about a certain change in the state of a system by performing work on the system under adiabatic conditions.
The amount of work needed is path dependent.
Work alone can not bring out such a change of state.
The amount of work needed is independent of path.
More information is needed to conclude anything about the path dependence or otherwise of the work needed.

The amount of work needed is path dependent.

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For a constant pressure reversible process, the enthalpy change (delta-H) of the system is
Cv.dT
Cp.dT
integ Cv.dT
integ Cp.dT

integ Cv.dT

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The work done in isothermal compression compared to that in adiabatic compression will be
less
more
same
more or less depending upon the extent of work done

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For organic compounds, group contribution method can be used for the estimation of
critical properties.
specific gravity.
specific volume.
thermal conductivity.

critical properties.

group contributin critical properties

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Specific __________ does not change during phase change at constant temperature and pressure.
entropy
Gibbs energy
internal energy
enthalpy

Gibbs energy

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When liquid and vapour phases of one component system are in equilibrium (at a given temperature and pressure), the molar free energy is
more in vapour phase.
more in liquid phase.
same in both the phases.
replaced by chemical potential which is more in vapour phase.

same in both the phases.

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Heat evolved/absorbed during conversion of a substance from one allotropic form to another is termed as the heat of
fusion
vaporisation
transition
none of these

transition

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What happens in a reversible adiabatic compression ?
Heating occurs
Cooling occurs
Pressure is constant
Temperature is constant

Heating occurs

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Sublimation temperature of dry ice (solid CO2) is __________ C.
-273
0
-78
5

-78

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If atmospheric temperature and dew point are nearly equal, then the relative humidity is
zero
0.5
almost 100%
unpredictable

almost 100%

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Entropy change in case of reversible adiabatic process is
minimum
zero
maximum
indeterminate

zero

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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 more less same unpredictable; depends on the particular reaction

same

The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be more less same data insufficient to predict

Mollier chart is a __________ plot. pressure vs enthalpy pressure vs volume enthalpy vs entropy temperature vs entropy

enthalpy vs entropy

Variation of equilibrium pressure with temperature for any two phases of a given substances is given by the __________ equation. Gibbs-Duhem Maxwell's Clayperon none of these

Clayperon

Pick out the undesirable property for a good refrigerant. high thermal conductivity low freezing point large latent heat of vaporisation high viscosity

high viscosity

Isotherm on an enthalpy-concentration diagram, for an ideal solution will be a straight line sine curve parabola hyperbola

straight line

The fusion of a crystalline solid at its melting point to form a liquid at the same temperature is accompanied by decrease in enthalpy corresponding to evolution of heat. decrease of entropy. increase in enthalpy corresponding to absorption of heat. no change in enthalpy.

increase in enthalpy corresponding to absorption of heat. ## Footnote fusion o crystalline - enthalpy increase

Melting of ice is an example of an __________ process. adiabatic isothermal isometric none of these

isothermal

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. 448 224 22.4 data insufficient; can't be computed

448

Rotary lime kiln is an example of a/an __________ system. closed open isolated non-thermodynamic

open

Heat of reaction is dependent on pressure only. dependent on temperature only. dependent on both pressure and temperature. independent of temperature changes.

dependent on both pressure and temperature.

The expression, , is for the____of an ideal gas. compressibility work done under adiabatic contition work done under isothermal condition co-efficient of thermal expansion

work done under isothermal condition

What happens in a reversible adiabatic expansion process ? Heating takes place. Cooling takes place. Pressure is constant. Temperature is constant.

Cooling takes place.

Degree of freedom of a system consisting of a gaseous mixture of H2 and NH3 will be 0 1 2 3

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 (aP/aV)s and the slope of the reversible isothermal line (aP/aV)T are related as (where, y = Cp/Cv) (aP/aV)S = (aP/aV)T (aP/aV)S = [(aP/aV)T]^Y (aP/aV)S = y(aP/aV)T (aP/aV)S = 1/y(aP/aV)T

(aP/aV)S = y(aP/aV)T

Pick out the wrong statement. The net change in entropy in any reversible cycle is always zero. The entropy of the system as a whole in an irreversible process increases. The entropy of the universe tends to a maximum. The entropy of a substance does not remain constant during a reversible adiabatie change.

The entropy of the universe tends to a maximum. ## Footnote wrong maximum entropy universe

Fugacity co-efficient of a substance is the ratio of its fugacity to mole fraction activity pressure activity co-efficient

activity co-efficient

Dryness fraction of wet steam is defined as the ratio of mass of vapour in the mixture to the mass of mixture __________ calorimeter is not used for measuring the dryness fraction of steam. Bomb Separating Bucket Throttling

Bomb

As the time is passing, entropy of the universe is increasing is decreasing remains constant data insufficient, can't be predicted

is increasing

Which of the following processes can not be made reversible even under ideal condition of operation? Free expansion of a gas. Compression of air in a compressor. Expansion of steam in a turbine. all of these.

Free expansion of a gas.

The relation connecting the fugacities of various components in a solution with one another and to composition at constant temperature and pressure is called the __________ equation. Gibbs-Duhem Van Laar Gibbs-Helmholtz Margules

Gibbs-Duhem

Which of the following identities can be most easily used to verify steam table data for superheated steam. (aT/aV)S = (ap/aS)V (aT/aP)S = (aV/aS)P (aP/aT)V = (aS/aV)T (aV/aT)P = -(aS/aP)T

(aV/aT)P = -(aS/aP)T

In the equation PVn = constant, if the value of n = y = Cp/Cv, then it represents a reversible __________ process. isothermal adiabatic isentropic polytropic

isentropic

The ammonia synthesis reaction represented by N2 + 3H2 <~> 2NH3 ; delta-H = - 22.4 kcal, is endothermic exothermic isothermal adiabatic

exothermic

With increase in temperature, the atomic heat capacities of all solid elements increases decreases remains unchanged decreases linearly

increases

The temperature at the eutectic point of the system is the __________ temperature that can be attained in the system. lowest highest average none of these

lowest

The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is less pronounced more pronounced equal data insufficient, can't be predicted.

more pronounced

Steam undergoes isentropic expansion in a turbine from 5000 kPa and 400 C (entropy = 6.65 kJ/kg K) to 150 kPa) (entropy of saturated liquid = 1.4336 kJ/kg . K, entropy of saturated vapour = 7.2234 kJ/kg. K) The exit condition of steam is superheated vapour. partially condensed vapour with quality of 0.9. saturated vapour. partially condensed vapour with quality of 0.1.

superheated vapour.

An isentropic process is carried out at constant volume pressure temperature all of these

volume

All gases except __________ shows a cooling effect during throttling process at atmospheric temperature and pressure. oxygen nitrogen air hydrogen

hydrogen

High pressure steam is expanded adiabati-cally 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 delta-H and delta-S respectively for this process: delta- H = 0 and delta-S = 0. delta- H is not equal to 0 and delta-S = 0. delta- H is not equal to 0 and delta-S is not equal to 0. delta- H = 0 and delta-S is not equal to 0.

delta- H is not equal to 0 and delta-S = 0.

The necessary condition for phase equilibrium in a multiphase system of N components is that the chemical potentials of a given component should be equal in all phases. chemical potentials of all components should be same in a particular phase. sum of the chemical potentials of any given component in all the phases should be the same. none of these.

chemical potentials of a given component should be equal in all phases.

Compressibility factor-reduced pressure plot on reduced co-ordinates facilitates use of only one graph for all gases. covering of wide range. easier plotting. more accurate plotting.

use of only one graph for all gases.

Which of the following is not an intensive property ? Molar heat capacity Internal energy Viscosity None of these

Internal energy

Pick out the wrong statement. At constant pressure, solubility of a gas in a liquid diminishes with rise in temperature. Normally, the gases which are easily liquified, are more soluble in common solvents. The gases which are capable of forming ions in aqueous solution, are much more soluble in water than in other solvents. At constant pressure, solubility of a gas in a liquid increases with rise in temperature.

At constant pressure, solubility of a gas in a liquid diminishes with rise in temperature.

Gibbs phase rule finds application, when heat transfer occurs by conduction convection radiation condensation

condensation ## Footnote condensation - gibbs phare rule

Absorption/evolution of heat during conversion of a substance from one allotropic form to another is termed as the heat of sublimation fusion transition vaporisation

transition

Ideal gas law is applicable at low T, low P high T, high P low T, high P high T, low P

high T, low P

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.

pressure to critical pressure.

For a reversible process involving only pressure-volume work (dF)T, p < 0 (dF)T, p > 0 (dF)T, p = 0 (dA)T, v < 0

(dF)T, p = 0

Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = Cp/Cv = 7/5) and the process to be reversible, is 300(32/7) 300(33/5) 300(333/7) 300(35/7)

300(32/7)

Entropy change for an irreversible process taking system and surrounding together is 0 > 0 < 0 none of these

> 0

In a homogeneous solution, the fugacity of a component depends upon the pressure composition temperature all of these

all of these

For an incompressible fluid, the __________ is a function of both pressure as well as temperature. internal energy enthalpy entropy all of these

enthalpy

An ideal monoatomic gas is taken round the cycle ABCDA as shown below in the P-V diagram (1) The work done during the cycle is PV 2PV PV/2 0

One ton of refrigeration capacity is equivalent to the heat removal rate of 50 k cal/hr 200 BTU/hr 200 BTU/minute 200 BTU/day

200 BTU/minute

What is the degree of freedom for a system comprising liquid water equilibrium with its vapour ? 0 1 2 3

Equilibrium constant of a reaction varies with the initial concentration of the reactant. pressure. temperature. none of these.

temperature.

Third law of thermodynamics is concerned with the value of absolute entropy. energy transfer. direction of energy transfer. none of these.

value of absolute entropy.

Claude's liquefaction process employs the cooling of gases by expansion in an engine following a constant pressure cycle throttling none of these

expansion in an engine

Gibbs free energy (F) is defined as F = E - TS F = H - TS F = H + TS F = E + TS

F = H - TS

The expression for entropy change given by, delta-S = nR ln (V2/V1) + nCv ln (T2/T1) is valid for reversible isothermal volume change. heating of a substance. cooling of a substance. simultaneous heating and expansion of an ideal gas.

simultaneous heating and expansion of an ideal gas.

The second law of thermodynamics states that the energy change of a system undergoing any reversible process is zero. it is not possible to transfer heat from a lower temperature to a higher temperature. the total energy of system and surrounding remains the same. none of the above.

none of the above.

Internal energy of an ideal gas increases with increase in pressure. decreases with increase in temperature. is independent of temperature. none of these.

none of these.

A refrigerator works on the principle of __________ law of thermodynamics. zeroth first second third

second

Pick out the wrong statement. The conversion for a gas phase reaction increases with decrease in pressure, if there is an increase in volume accompanying the reaction. With increase in temperature, the equilibrium constant increases for an exothermic reaction. The equilibrium constant of a reaction depends upon temperature only. The conversion for a gas phase reaction increases with increase in pressure, if there is a decrease in volume accompanying the reaction.

With increase in temperature, the equilibrium constant increases for an exothermic reaction.

Pick out the wrong statement. Enthalpies of all elements in their standard states are assumed to be zero. Combustion reactions are never en-dothermic in nature. Heat of reaction at constant volume is equal to the change in internal energy. Claussius-clayperon equation is not applicable to melting process.

Claussius-clayperon equation is not applicable to melting process.

Which of the following is affected by the temperature ? Fugacity Activity co-efficient Free energy all of these

all of these

The molar excess Gibbs free energy, g^E, for a binary liquid mixture at T and P is given by, (g^E/RT) = A . x1. x2, where A is a constant. The corresponding equation for ln y1, where y1 is the activity co-efficient of component 1, is A . X2^2 Ax1 Ax2 Ax1^2

A . X2^2

The adiabatic throttling process of a perfect gas is one of constant enthalpy in which there is a temperature drop. which is exemplified by a non-steady flow expansion. which can be performed in a pipe with a constriction. in which there is an increase in temperature.

which can be performed in a pipe with a constriction.

For spontaneous changes in an isolated system (S = entropy) ds = 0 ds <0 ds > 0 ds = Constant

ds > 0

A gas performs the maximum work, when it expands non-uniformly adiabatically isobarically isothermally

isobarically

There is a change in __________ during the phase transition. volume pressure temperature all a, b & c

volume

Which of the following is Virial equation of state? (p + a/V^2)(V - b) = nRT PV = nRT PV = A + B/V + C/V^2 + D/V^3 + ...

PV = A + B/V + C/V^2 + D/V^3 + ...

Pressure-enthalpy chart is useful in refrigeration. The change in internal energy of an ideal fluid used in ideal refrigeration cycle is positive negative zero infinity

zero

First law of thermodynamics deals with the direction of energy transfer. reversible processes only. irreversible processes only. none of these.

direction of energy transfer.

Henry's law is closely obeyed by a gas, when its __________ is extremely high. pressure solubility temperature none of these

none of these

A solute distributes itself between two non-miscible 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 Margule's equation. a corollary of Henry's law. none of these.

the distribution law.

A solid is transformed into vapour without going to the liquid phase at triple point boiling point below triple point always

triple point

A gas mixture of three components is brought in contact with a dispersion of an organic phase in water. The degree of freedom of the system are 4 3 5 6

1m^3 of an ideal gas at 500 K and 1000 kPa expands reversibly to 5 times its initial volume in an insulated container. If the specific heat capacity (at constant pressure) of the gas is 21 J/mole . K, the final temperature will be 35 K 174 K 274 K 154 K

274 K

For a thermodynamic system containing 'x' chemical species, the maximum number of phases that can co-exist at equilibrium is x x + 1 x + 2 x + 3

x + 2

A reasonably general expression for vapour-liquid phase equilibrium at low to moderate pressure is phi-i yi P = Yi xi fi where, phi 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.

temperature, pressure and liquid composition xi only.

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/cm^2 15 C and 1 kgf/cm^2

0 C and 750 mm Hg

Normal temperature and pressure (N.T.P.) corresponds to 0 C and 760 mm Hg. 15 C and 760 mm Hg. 20 C and 760 mm Hg. 0 C and 1 kgf/cm^2.

20 C and 760 mm Hg.

The minimum number of phases that can exist in a system is 0 1 2 3

Enthalpy changes over a constant pressure path are always zero for __________ gas. any a perfect an easily liquefiable a real

a perfect

The fugacity of a gas in a mixture is equal to the product of its mole fraction and its fugacity in the pure state at the total pressure of the mixture". This is the statement as per Gibbs-Helmholtz called Lewis-Randall rule Henry's law none of these

called Lewis-Randall rule

__________ does not change during phase transformation processes like sublimation, melting & vaporisation. Entropy Gibbs free energy Internal energy all of these

Gibbs free energy

Which one is true for a throttling process ? A gas may have more than one inversion temperatures. The inversion temperature is different for different gases. The inversion temperature is same for all gases. The inversion temperature is the temperature at which Joule-Thomson co-efficient is infinity.

The inversion temperature is different for different gases.

Choose the condition that must be specified in order to liquify CO2 (triple point for CO2 is - 57 C and 5.2 atm). Pressure must be kept below 5.2 atm. Temperature must be kept above - 57 C. Pressure must be kept below 5.2 atm. and temperature must be kept above 57 C. Pressure and temperature must be kept below 5.2 atm. and - 57 C respectively.

Pressure and temperature must be kept below 5.2 atm. and - 57 C respectively.

One mole of nitrogen at 8 bar and 600 K is contained in a piston-cylinder arrangement. It is brought to 1 bar isothermally against a resisting pressure of 1 bar. The work done (in Joules) by the gas is 30554 10373 4988.4 4364.9

10373

Lenz's law results from the law of conservation of mass momentum energy none of these

energy ## Footnote LLE Lenz's law enegy

In the equation, PVn = constant, if the value of n is in between 1 and y (i.e. Cp/Cv), then it represents a reversible __________ process. isometric polytropic isentropic isobaric

polytropic

Throttling process is a/an __________ process. reversible and isothermal irreversible and constant enthalpy reversible and constant entropy reversible and constant enthalpy

irreversible and constant enthalpy ## Footnote throttling - irrev.const.ent.

The main feature of Carnot refrigeration cycle is that, it does not need the addition of external work for its functioning. transfers heat from high temperature to low temperature. accomplishes the reverse effect of the heat engine. none of these.

accomplishes the reverse effect of the heat engine.

Charles' law for gases states that V/2 = Constant V infinity 1/T V infinity 1/p PV/T = Constant

V/2 = Constant

If heat contents of CH4, C2H4 and C3H8 are -17.9, 12.5 and -24.8 kcal/mole respectively, than delta-H for the reaction CH4(g) + C2H4(g) C3H8(g) will be __________ Kcal. -19.4 -30.2 55.2 -55.2

-19.4

Helmholtz free energy (A) is defined as A = H - TS A = E - TS A = H + TS none of these

A = E - TS

As pressure approaches zero, the ratio of fugacity to pressure (f/P) for a gas approaches zero unity infinity an indeterminate value

unity

For any system, what is the minimum number of degrees of freedom? 1 0 2 3

At 60 C, vapour pressure of methanol and water are 84.562 kPa and 19.953 kPa respectively. An aqueous solution of methanol at 60 C exerts a pressure of 39.223 kPa; the liquid phase and vapour phase mole fractions of methanol are 0.1686 and 0.5714 respectively. Activity co-efficient of methanol is 1.572 1.9398 3.389 4.238

1.572

The variation of heat of reaction with temperature at constant pressure is given by the __________ law. Kelvin's Antonie's Kirchoffs none of these

Kirchoffs

At absolute zero temperature, the __________ of the gas is zero. pressure volume mass none of these

volume

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 of these

all of these

The equation, , applicable to a binary solution of components. A and B in equilibrium with their vapors at constant temperature and pressure is called the __________ equation. Van Laar Margules Gibbs-Duhem Gibbs-Duhem-Margules

Gibbs-Duhem-Margules

Entropy of a substance remains constant during a/an __________ change. reversible isothermal irreversible isothermal reversible adiabatic none of these

reversible adiabatic

Gases are cooled in Joule-Thomson expansion, when it is __________ inversion temperature. below at above either 'b' or 'c'

below

PVy = constant, holds good for an isentropic process, which is reversible and isothermal. isothermal and irreversible. reversible and adiabatic. adiabatic and irreversible.

reversible and adiabatic.

Which of the following behaves most closely like an ideal gas ? He N2 O2 H2

In the reaction, C + O2 -> CO2 ; delta-H = - 94 kcal. What is the heat content (enthalpy)of O2? -94 kcal > -94 kcal < - 94 kcal zero

zero

When a system is in equilibrium for all possible processes, the differential or finite change of entropy is < 0 > 0 0 none of these

< 0

A system is said to be at equilibrium, if the entropy of the system has reached __________ value. minimum zero maximum none of these

maximum

In the equation, PV^n = constant, if the value of n = +- infinity, then it represents a reversible __________ process. adiabatic isometric isentropic isothermal

isometric

Degree of freedom of the system ice-water-vapour will be 0 1 2 3

A system in which there is exchange of energy but not of mass, is called a/an __________ system. isolated open insulated closed

closed

The point at which all the three (solid, liquid and gas) phases co-exist, is known as the __________ point. freezing triple boiling Boyle

triple

In an ideal gas mixture, fugacity of a species is equal to its vapor pressure partial pressure chemical potential none of these

partial pressure

The third law of thermodynamics states that the heat capacity of a crystalline solid is zero at absolute zero temperature. heat transfer from low temperature to high temperature source is not possible without external work. gases having same reduced properties behave similarly. none of these.

heat capacity of a crystalline solid is zero at absolute zero temperature.

Consider the reaction, C + O2 <~> CO2 ;delta-H = - 94 kcal. What will be the value of delta-H for the reaction CO2 C + O2 ? -94 kcal + 94 kcal > 94 kcal < -94 kcal

+ 94 kcal

Which is not a state function ? Specific volume Work Pressure Temperature

Work

For an ideal liquid solution, which of the following is unity ? Activity Fugacity Activity co-efficient Fugacity co-efficient

Activity co-efficient

In the decomposition of PCl5 represented by, PCl5 <~> PCl3 + Cl2, decrease in the pressure of the system will __________ the degree of dissociation of PCl5. increase decrease not alter none of these

increase

To obtain integrated form of Clausius-Clayperon equation,(1), from the exact Clayperon equafion, it is assumed that the volume of the liquid phase is negligible compared to that of vapour phase. vapour phase behaves as an ideal gas. heat of vaporisation is independent of temperature. all of these.

all of these.

In case of an __________ process, the temperature of the system increases. isothermal compression isothermal expansion adiabatic expansion adiabatic compression

adiabatic compression

Cp of a gas at its critical temperature and pressure becomes zero. becomes infinity. equals 1 kcal/kmol K. equals 0.24 kcal/kmol K.

equals 1 kcal/kmol K.

Trouton's ratio is given by (where lambda-b, = molal heat of vaporisation of a substance at its normal boiling point, kcal/kmol Tb = normal boiling point, K ) lambda-b/Tb Tb/lambda-b sqrt(lambda-b/Tb) sqrt(Tb/lambda-b)

lambda-b/Tb

Which of the following is true for Virial equation of state ? Virial co-efficients are universal constants. Virial co-efficients 'B' represents three body interactions. Virial co-efficients are function of temperature only. For some gases, Virial equations and ideal gas equations are the same.

Virial co-efficients are function of temperature only.

Molar heat capacity of water in equilibrium with ice at constant pressure is __________ Kcal/kg mole . K 0 ∞ 50 100

∞

A gas can be liquified by pressure alone only, when its temperature is __________ its critical temperature. less than more than equal to or higher than less than or equal to

less than or equal to

For an ideal gas, the internal energy depends upon its __________ only. molecular size temperature volume pressure

temperature

Compound having large heat of formation is more stable. less stable. not at all stable (like nascent O2). either more or less stable ; depends on the compound.

more stable.

Second law of thermodynamics is concerned with the amount of energy transferred. direction of energy transfer. irreversible processes only. non-cyclic processes only.

direction of energy transfer.