Free energy, fugacity and activity co-efficient are all affected by change in the temperature. The fugacity co-efficient of a gas at constant pressure ____with the increase of reduced temperature.
Decreases
Increases
Remains constant
Decreases logarithmically
Correct Answer :
B. Increases
Related Questions
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)
Heat of reaction at constant volume is identified with __________ change.
Enthalpy
Internal energy
Either (A) or (B)
Neither (A) nor (B)
The entropy change in a reversible isothermal process, when an ideal gas expands to four times its initial volume is
R loge 4
R log10 4
Cv log10 4
Cv loge 4
COP of a refrigerator drawing 1 kW of power per ton of refrigeration is about
0.5
3.5
4.5
8.5
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
Which of the following is an undesirable characteristic of a refrigerant?
It should be non-explosive
It should have a sub-atmospheric vapor pressure at the temperature in refrigerator coils
Its vapor pressure at the condenser temperature should be very high
None of these
The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances. This is the
Lewis-Randall rule
Statement of Van't Hoff Equation
Le-Chatelier's principle
None of these
During Joule-Thomson expansion of gases
Enthalpy remains constant
Entropy remains constant
Temperature remains constant
None of these
The activity of an ideal gas is numerically __________ its pressure.
More than
Less than
Equal to
Data insufficient, can't be predicted
In a P-V diagram (for an ideal gas), an isothermal curve will coincide within adiabatic curve (through a point), when
Cp < Cv
Cp = Cv
Cp > Cv
C ≥ Cv
In the reaction; N2 + O2 2NO, increasing the pressure will result in
Shifting the equilibrium towards right
Shifting the equilibrium towards left
No change in equilibrium condition
None of these
Out of the following refrigeration cycles, which one has the minimum COP (Co-efficient of performance)?
Air cycle
Carnot cycle
Ordinary vapour compression cycle
Vapour compression with a reversible expansion engine
Specific/molar Gibbs free energy for a pure substance does not change during
Sublimation
Vaporisation
Melting
Either (A), (B) or (C)
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
Ideal refrigeration cycle is
Same as Carnot cycle
Same as reverse Carnot cycle
Dependent on the refrigerant's properties
The least efficient of all refrigeration processes
The gas law (PV = RT) is true for an __________ change.
Isothermal
Adiabatic
Both (A) & (B)
Neither (A) nor (B)
An isolated system can exchange __________ with its surroundings.
Matter
Energy
Neither matter nor energy
Both matter and energy
The most important application of distribution law is in
Evaporation
Liquid extraction
Drying
Distillation
In case of steady flow compression polytropic process (PVn = constant), the work done on air is the lowest, when
n = y = 1.4
n = 0
n = 1
n = 1.66
Which of the following is not correct for a reversible adiabatic process?
TVγ-1 = constant
p1-γ.TY = constant
PVγ = constant
None of these
The variation of heat of reaction with temperature at constant pressure is given by the __________ law.
Kelvin's
Antoines
Kirchoffs
None of these
Domestic refrigerator usually works on the __________ refrigeration cycle.
Carnot
Air
Absorption
vapour-ejection
Heating of water under atmospheric pressure is an __________ process.
Isochoric
Isobaric
Adiabatic
Isothermal
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
(∂T/∂P)H is the mathematical expression for
Specific heat at constant pressure (Cp)
Specific heat at constant volume (Cv)
Joule-Thompson co-efficient
None of these
The quantitative effect of temperature on chemical equilibrium is given by the
Vant-Hoff equation
Le-Chatelier's principle
Arrhenius equation
None of these
Fugacity of a component in an ideal gas mixture is equal to the partial pressure of that component in the mixture. The fugacity of each component in a stable homogeneous solution at constant pressure and temperature __________ as its mole fraction increases.
Decreases
Decreases exponentially
Increases
Remain constant
Pick out the wrong statement
Phase rule variables are intensive properties
Heat and work are both state function
The work done by expansion of a gas in vacuum is zero
CP and CV are state function
Pick out the correct statement:
In an isothermal system, irreversible work is more than reversible work
Under reversible conditions, the adiabatic work is less than isothermal work
Heat, work, enthalpy and entropy are all 'state functions'
Matter and energy cannot be exchanged with the surroundings in a closed system
The chemical potential of a component (μi) of a phase is the amount by which its capacity for doing all work, barring work of expansion is increased per unit amount of substance added for an infinitesimal addition at constant temperature and pressure. It is given by
(∂E/∂ni)S, v, nj
(∂G/∂ni)T, P, nj = (∂A/∂ni) T, v, nj
(∂H/∂ni)S, P, nj
All (A), (B) and (C)