Pick out the wrong statement.
The net change in entropy in any reversible cycle is always zero
The entropy of the system as a whole in an irreversible process increases
The entropy of the universe tends to a maximum
The entropy of a substance does not remain constant during a reversible adiabatic change
Correct Answer :
D. The entropy of a substance does not remain constant during a reversible adiabatic change
Related Questions
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
The internal energy of an ideal gas does not change in a reversible __________ process.
Isothermal
Adiabatic
Isobaric
Isometric
Fundamental principle of refrigeration is based on the __________ law of thermodynamics.
Zeroth
First
Second
Third
With increase in compression ratio, the efficiency of the otto engine
Increases
Decreases
Remain constant
Increases linearly
The difference between isothermal compressibility and adiabatic compressibility for an ideal gas is
0
+ve
-ve
∞
In a homogeneous solution, the activity coefficient of a component depends upon the
Pressure
Composition
Temperature
All (A), (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
Specific heat of a gas for a reversible adiabatic process is
Negative
Zero
Infinity
None of these
The absolute entropy for all crystalline substances at absolute zero temperature is
Zero
Negative
More than zero
Indeterminate
The first law of thermodynamics is a restatement of the law of conservation of
Mass
Energy
Momentum
None of these
Second law of thermodynamics is concerned with the
Amount of energy transferred
Direction of energy transfer
Irreversible processes only
Non-cyclic processes only
The principle applied in liquefaction of gases is
Adiabatic expansion
Joule-Thomson effect
Both (A) and (B)
Neither (A) nor (B)
Adiabatic compression of a saturated water vapour makes it
Supersaturated
Superheated
Both (A) and (B)
Neither (A) nor (B)
In the equation PVn = constant, if the value of n = y = Cp/Cv, then it represents a reversible __________ process.
Isothermal
Adiabatic
Isentropic
Polytropic
The equation, Cp - Cv = R, is true for __________ gas.
No
Any real
Only ideal
Both (B) and (C)
The main feature of Carnot refrigeration cycle is that, it
Does not need the addition of external work for its functioning
Transfers heat from high temperature to low temperature
Accomplishes the reverse effect of the heat engine
None of these
Lenz's law results from the law of conservation of
Mass
Momentum
Energy
None of these
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
Pick out the wrong statement.
Minimum number of degree of freedom of a system is zero
Degree of freedom of a system containing a gaseous mixture of helium, carbon dioxide and hydrogen is 4
For a two phase system in equilibrium made up of four non-reacting chemical species, the number of degrees of freedom is 4
Enthalpy and internal energy change is zero during phase change processes like melting, vaporisation and sublimation
Melting of ice exemplifies a/an
Adiabatic process
Endothermic reaction
Exothermic reaction
Process involving a chemical reaction
If we increase the pressure on a substance (which is at its triple point), then the triple point
Increases
Decreases
Remains unchanged
May increase or decrease; depends on the substance
Pick out the wrong statement.
The net change in entropy in any reversible cycle is always zero
The entropy of the system as a whole in an irreversible process increases
The entropy of the universe tends to a maximum
The entropy of a substance does not remain constant during a reversible adiabatic change
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)
Entropy change of the reaction, H2O (liquid) → H2O (gas), is termed as the enthalpy of
Solution
Vaporisation
Formation
Sublimation
Pick out the wrong statement.
Activity co-efficient is dimensionless.
In case of an ideal gas, the fugacity is equal to its pressure.
In a mixture of ideal gases, the fugacity of a component is equal to the partial pressure of the component.
The fugacity co-efficient is zero for an ideal gas
Equilibrium constant decreases as the temperature
Increases, for an exothermic reaction
Decreases, for an exothermic reaction
Increases, for an endothermic reaction
None of these
Requisites of a reversible process is that the
System and surroundings pressure be equal
Friction in the system should be absent
System and surroundings temperature be equal
None of these
Gibbs free energy at constant pressure and temperature under equilibrium conditions is
∞
0
Maximum
Minimum
1m3 of an ideal gas at 500 K and 1000 kPa expands reversibly to 5 times its initial volume in an insulated container. If the specific heat capacity (at constant pressure) of the gas is 21 J/mole . K, the final temperature will be
35 K
174 K
274 K
154 K
For an ideal gas, the activity co-efficient is
Directly proportional to pressure
Inversely proportional to pressure
Unity at all pressures
None of these