What is the value of Joule-Thomson co-efficient for an ideal gas?
+ve
-ve
0
∞
Correct Answer :
C. 0
Related Questions
Specific __________ does not change during phase change at constant temperature and pressure.
Entropy
Gibbs energy
Internal energy
Enthalpy
During adiabatic expansion of gas
Pressure remains constant
Pressure is increased
Temperature remains constant
None of these
Which of the following is a widely used refrigerant in vapour compression refrigeration system (using large centrifugal compressor)?
Freon
Liquid sulphur dioxide
Methyl chloride
Ammonia
Pick out the correct statement.
The available energy in an isolated system for all irreversible (real) processes decreases
The efficiency of a Carnot engine increases, if the sink temperature is decreased
The reversible work for compression in non-flow process under isothermal condition is the change in Helmholtz free energy
All (A), (B) and (C)
No work is done by the system, when a reaction occurs at constant
Volume
Temperature
Pressure
None of these
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
A refrigeration cycle is the same as a __________ cycle,
Turbine
Heat engine
Reversed heat engine
None of these
The number of degree of freedom for an Azeotropic mixture of ethanol and water in vapourliquid equilibrium, is
3
1
2
0
When a gas is subjected to adiabatic expansion, it gets cooled due to
Decrease in velocity
Decrease in temperature
Decrease in kinetic energy
Energy spent in doing work
The standard state of a gas (at a given temperature) is the state in which fugacity is equal to
Unity
Activity
Both (A) & (B)
Neither (A) nor (B)
Which law of the thermodynamics provides basis for measuring the thermodynamic property?
First law
Zeroth law
Third law
Second law
Air-refrigeration cycle
Is the most efficient of all refrigeration cycles
Has very low efficiency
Requires relatively large quantities of air to achieve a significant amount of refrigeration
Both (B) and (C)
Gibbs free energy per mole for a pure substance is equal to the
Latent heat of vaporisation
Chemical potential
Molal boiling point
Heat capacity
The expression, ΔG = nRT. ln(P2/P1), gives the free energy change
With pressure changes at constant temperature
Under reversible isothermal volume change
During heating of an ideal gas
During cooling of an ideal gas
The internal energy of an ideal gas is a function of its __________ only.
Molecular size
Volume
Pressure
Temperature
Pick out the wrong statement.
A closed system does not permit exchange of mass with its surroundings but may permit exchange of energy.
An open system permits exchange of both mass and energy with its surroundings
The term microstate is used to characterise an individual, whereas macro-state is used to designate a group of micro-states with common characteristics
None of the above
In case of the decomposition of hydroiodic acid (2HI H2 + I2), addition of H2 (at equilibrium condition) will
Increase the partial pressure of I2
Decrease the partial pressure of HI
Diminish the degree of dissociation of HI
None of these
The Carnot co-efficient of performance (COP) of a domestic air conditioner compared to a household refrigerator is
Less
More
Same
Dependent on climatic conditions
The equation, PV = nRT, is best obeyed by gases at
Low pressure & high temperature
High pressure & low temperature
Low pressure & low temperature
None of these
High __________ is an undesirable property for a good refrigerant.
Specific heat
Latent heat of vaporisation
Viscosity
Specific vapor volume
Gibbs-Helmholtz equation is
ΔF = ΔH + T [∂(ΔF)/∂T]P
ΔF = ΔH - TΔT
d(E - TS) T, V < 0
dP/dT = ΔHvap/T.ΔVvap
Solubility of a substance which dissolves with an increase in volume and liberation of heat will be favoured by the
Low pressure and high temperature
Low pressure and low temperature
High pressure and low temperature
High pressure and high temperature
Which is a state function?
Specific volume
Work
Pressure
Temperature
If the internal energy of an ideal gas decreases by the same amount as the work done by the system, then the
Process must be isobaric
Temperature must decrease
Process must be adiabatic
Both (B) and (C)
What is the number of degree of freedom for a system of two miscible non-reacting species in vapor-liquid equilibrium forming an azeotrope?
0
2
1
3
Which of the following is Clausius-Clapeyron Equation for vaporisation of an ideal gas under the condition that the molar volume of liquid is negligible compared to that of the vapor?
d ln p/dt = Hvap/RT2
d ln p/dt = RT2/Hvap
dp/dt = RT2/Hvap
dp/dt = Hvap/RT2
Which of the following decreases with increase in pressure?
Melting point of ice
Melting point of wax
Boiling point of liquids
None of these
Lenz's law results from the law of conservation of
Mass
Momentum
Energy
None of these
For an ideal gas, the internal energy depends upon its __________ only.
Molecular size
Temperature
Volume
Pressure
Degree of freedom of the system ice-watervapour will be
0
1
2
3