Which is a state function?
Specific volume
Work
Pressure
Temperature
Correct Answer :
B. Work
Related Questions
In which of the following reaction equilibrium, the value of equilibrium constant Kp will be more than is Kc?
2HI H2 + I2
N2O4 2NO2
2SO2 + O2 2SO3
None of these
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)
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
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
Equation which relates pressure, volume and temperature of a gas is called the
Equation of state
Gibbs Duhem equation
Ideal gas equation
None of these
Tea kept in a thermos flask is vigorously shaken. If the tea is considered as a system, then its temperature will
Increase
Decrease
Remain unchanged
First fall and then rise
If two gases have same reduced temperature and reduced pressure, then they will have the same
Volume
Mass
Critical temperature
None of these
Internal energy of an element at 1 atm and 25° C is __________ kcal/kg.mole.
0
273
25
None of these
Which of the following processes cannot 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 (A), (B) & (C)
Compressibility factor for almost all the gases are approximately same at the same
Pressure and temperature
Reduced pressure and reduced temperature
Critical pressure and critical temperature
None of these
The necessary and sufficient condition for equilibrium between two phases is
The concentration of each component should be same in the two phases
The temperature of each phase should be same
The pressure should be same in the two phases
The chemical potential of each component should be same in the two phases
Gases are cooled in Joule-Thomson expansion, when it is __________ inversion temperature.
Below
At
Above
Either 'b' or 'c'
Entropy, which is a measure of the disorder of a system, is:
Independent of pressure
Independent of temperature
Zero at absolute zero temperature for a perfect crystalline substance
All (A), (B) & (C)
For a multi-component system, the term chemical potential is equivalent to the
Molal concentration difference
Molar free energy
Partial molar free energy
Molar free energy change
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
Which of the following equations is obtained on combining 1st and 2nd law of thermodynamics, for a system of constant mass?
dE = Tds - PdV
dQ = CvdT + PdV
dQ = CpdT + Vdp
Tds = dE - PdV
The intensive properties are
Molar volume, density, viscosity and boiling point
Refractive index and surface tension
Both (A) and (B)
None of these
A system is said to be isopiestic, if there is no __________ change.
Temperature
Pressure
Volume
None of these
Which of the following units is not present in both the vapor compression refrigeration system and absorption refrigeration system?
Expansion valve
Condenser
Refrigerator
Compressor
The internal energy of an ideal gas does not change in a reversible __________ process.
Isothermal
Adiabatic
Isobaric
Isometric
The change in __________ is equal to the reversible work for compression in steady state flow process under isothermal condition.
Internal energy
Enthalpy
Gibbs free energy
Helmholtz free energy
At normal boiling point, molar entropy of vaporisation is __________ Joule/K°.mole.
72
92
142
192
At constant temperature and pressure, for one mole of a pure substance, the ratio of the free energy to the chemical potential is
Zero
One
Infinity
Negative
High pressure steam is expanded adiabatically 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 ΔH and ΔS respectively for this process:
Δ H = 0 and ΔS = 0
Δ H ≠ 0 and ΔS = 0
Δ H ≠ 0 and ΔS ≠ 0
Δ H = 0 and ΔS ≠ 0
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
Which of the following is not an equation of state?
Bertholet equation
Clausius-Clapeyron equation
Beattie-Bridgeman equation
None of these
1st law of thermodynamics is nothing but the law of conservation of
Momentum
Mass
Energy
None of these
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
On opening the door of an operating refrigerator kept in a closed room, the temperature of the room will
Increase
Decrease
Remain same
Increase in summer and will decrease in winter
For an irreversible process involving only pressure-volume work
(dF)T, p <0
(dF)T, p = 0
(dF)T, p > 0
(dA)T, v >0