All gases above its inversion temperature, in a throttling process will show
A heating effect
No change in temperature
A cooling effect
Either (A) or (C)
Correct Answer :
A. A heating effect
Related Questions
Which of the following units is not present in both the vapor compression refrigeration system and absorption refrigeration system?
Expansion valve
Condenser
Refrigerator
Compressor
In the equation, PVn = constant, if the value of n = 1, then it represents a reversible __________ process.
Isothermal
Isobaric
Polytropic
Adiabatic
__________ decreases during adiabatic throttling of a perfect gas.
Entropy
Temperature
Enthalpy
Pressure
The number of degrees of freedom for an azeotropic mixture in a two component vapour-liquid equilibria is/are
Zero
One
Two
Three
Heat requirement for decomposition of a compound into its elements is __________ that is evolved during the formation of that compound from its elements.
The same
Less than
Greater than
Different than
What is the value of Joule-Thomson co-efficient for an ideal gas?
+ve
-ve
0
∞
If the molar heat capacities (Cp or Cv) of the reactants and products of a chemical reaction are identical, then, with the increase in temperature, the heat of reaction will
Increase
Decrease
Remain unaltered
Increase or decrease; depends on the particular reaction
Free energy change at equilibrium is
Zero
Positive
Negative
Indeterminate
When a gas is expanded from high pressure region to low pressure region; temperature change occurs. This phenomenon is related to the
Gibbs-Duhem equation
Gibbs-Helmholtz equation
Third law of thermodynamics
Joule-Thomson effect
What is the number of degrees of freedom for liquid water in equilibrium with a mixture of nitrogen and water vapor?
2
0
3
1
Out of the following refrigeration cycles, which one has maximum COP?
Air cycle
Carnot cycle
Ordinary vapor compression cycle
Vapor compression with a reversible expansion engine
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
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
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 ln f
μ° + T ln f
μ° + R/T ln f
An isolated system can exchange __________ with its surroundings.
Matter
Energy
Neither matter nor energy
Both matter and energy
Enthalpy 'H' is defined as
H = E - PV
H = F - TS
H - E = PV
None of these
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
Partial molar free energy of an element A in solution is same as its
Chemical potential
Activity
Fugacity
Activity co-efficient
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
Which of the following is not an intensive property?
Molar heat capacity
Internal energy
Viscosity
None of these
Enthalpy changes over a constant pressure path are always zero for __________ gas.
Any
A perfect
An easily liquefiable
A real
The activity of an ideal gas is numerically __________ its pressure.
More than
Less than
Equal to
Data insufficient, can't be predicted
The variation of heat of reaction with temperature at constant pressure is given by the __________ law.
Kelvin's
Antoines
Kirchoffs
None of these
A system in which there is exchange of energy but not of mass, is called a/an __________ system.
Isolated
Open
Insulated
Closed
The ammonia synthesis reaction represented by N2 + 3H2 2NH3; ΔH = - 22.4 kcal, is
Endothermic
Exothermic
Isothermal
Adiabatic
Pick out the wrong statement pertaining to the decomposition of PCl5 represented by, PCl5 PCl3 + Cl2.Degree of dissociation of PCl5 will
Decrease on addition of Cl2
Increase on addition of an inert gas at constant pressure
Decrease on increasing the pressure of the system
None of these
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)
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)
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
The Maxwell relation derived from the differential expression for the Helmholtz free energy (dA) is
(∂T/∂V)S = - (∂P/∂S)V
(∂S/∂P)T = - (∂V/∂T)P
(∂V/∂S)P = (∂T/∂P)S
(∂S/∂V)T = (∂P/∂T)V