Clausius-Clapeyron equation is applicable to __________ equilibrium processes.
Solid-vapor
Solid-liquid
Liquid-vapor
All (A), (B) and (C)
Correct Answer :
D. All (A), (B) and (C)
Related Questions
Joule-Thomson experiment is
Isobaric
Adiabatic
Isenthalpic
Both (B) & (C)
Efficiency of a Carnot engine working between temperatures T1 and T2 (T1 < T) is
(T2 - T1)/T2
(T2 - T1)/T1
(T1 - T2)/T2
(T1 - T2)/T1
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 expression for the work done for a reversible polytropic process can be used to obtain the expression for work done for all processes, except reversible __________ process.
Isobaric
Isothermal
Adiabatic
None of these
Melting of wax is accompanied with __________ in entropy.
Increase
Decrease
No change
None of these
Charles' law for gases states that
V/T = Constant
V ∝ 1/T
V ∝ 1/P
PV/T = Constant
Heat of reaction at constant volume is identified with __________ change.
Enthalpy
Internal energy
Either (A) or (B)
Neither (A) nor (B)
No work is done by the system, when a reaction occurs at constant
Volume
Temperature
Pressure
None of these
The freezing point of a liquid decreases when the pressure is increased, if the liquid __________ while freezing.
Contracts
Expands
Does not change in volume
Either (A), (B) or (C)
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
Kopp's rule is used to calculate the heat capacity of
Solids
Liquids
Gases
All (A), (B) & (C)
Critical temperature is defined as the temperature above which a gas will
Not liquify (barring exceptions)
Immediately liquify
Never liquify however high the pressure may be
None of these
Maxwell's relation corresponding to the identity, dH = dS = Vdp + Σμi dni is
(∂T/∂V)S, ni = -(∂P/∂S)V, ni
(∂S/∂P)T, ni = (∂V/∂T)P, ni
(∂S/∂V)T, ni = (∂P/∂T)V, ni
(∂T/∂P)S, ni = (∂V/∂S)P, ni
All gases during throttling process at atmospheric temperature and pressure show a cooling effect except
CO2
H2
O2
N2
What happens in a reversible adiabatic expansion process?
Heating takes place
Cooling takes place
Pressure is constant
Temperature is constant
y = specific heat ratio of an ideal gas is equal to
Cp/Cv
Cp/(CP-R)
1 + (R/CV)
All (A), (B) and (C)
In the equation, PVn = constant, if the value of n = 1, then it represents a reversible __________ process.
Isothermal
Isobaric
Polytropic
Adiabatic
Refrigeration capacity of a household refrigerator may be round about __________ tons.
0.15
1.5
4.5
6.5
Which of the following is a thermodynamic property of a system?
Concentration
Mass
Temperature
Entropy
Entropy change of the reaction, H2O (liquid) → H2O (gas), is termed as the enthalpy of
Solution
Vaporisation
Formation
Sublimation
A change in state involving a decrease in entropy can be spontaneous, only if
It is exothermic
It is isenthalpic
It takes place isothermally
It takes place at constant volume
For a spontaneous process, free energy
Is zero
Increases
Decreases whereas the entropy increases
And entropy both decrease
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
Pick out the wrong statement.
A refrigeration cycle violates the second law of thermodynamics
Refrigeration cycle is normally represented by a temperature vs. entropy plot
In a refrigerator, work required decreases as the temperature of the refrigerator and the temperature at which heat is rejected increases
One ton of refrigeration is equivalent to the rate of heat absorption equal to 3.53 kW
Gibbs-Helmholtz equation is
ΔF = ΔH + T [∂(ΔF)/∂T]P
ΔF = ΔH - TΔT
d(E - TS) T, V < 0
dP/dT = ΔHvap/T.ΔVvap
At a given temperature, the volume of a gas dissolved in a solvent __________ with increase in pressure.
Increases
Decreases
Remains unchanged
May increase or decrease; depends on the gas
A solid is transformed into vapour without going to the liquid phase at
Triple point
Boiling point
Below triple point
Always
For a constant pressure reversible process, the enthalpy change (ΔH) of the system is
Cv.dT
Cp.dT
∫ Cp.dT
∫ Cv.dT
The value of gas constant 'R' is
1.987 cal/gm mole °K
1.987 BTU/lb. mole °R
Both (A) and (B)
Neither (A) nor (B)
A gas can be liquefied 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