A Carnot cycle consists of the following steps:
Two isothermal and two isentropic
Two isobaric and two isothermal
Two isochoric and two isobaric
Two isothermals and two isochoric
Correct Answer :
A. Two isothermal and two isentropic
Related Questions
Keeping the pressure constant, to double the volume of a given mass of an ideal gas at 27°C, the temperature should be raised to __________ °C.
270
327
300
540
Fundamental principle of refrigeration is based on the __________ law of thermodynamics.
Zeroth
First
Second
Third
The partial pressure of each constituent present in an alloy is __________ the total vapor pressure exerted by the alloy.
Less than
Equal to
More than
Either (B) or (C); depends on the type of alloy
Pick out the correct statement.
Like internal energy and enthalpy, the absolute value of standard entropy for elementary substances is zero
Melting of ice involves increase in enthalpy and a decrease in randomness
The internal energy of an ideal gas depends only on its pressure
Maximum work is done under reversible conditions
Pick out the wrong statement.
Trouton's ratio of non-polar liquids is calculated using Kistyakowsky equation
Thermal efficiency of a Carnot engine is always less than 1
An equation relating pressure, volume and temperature of a gas is called ideal gas equation
None of these
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
Trouton's ratio of __________ liquids is calculated using Kistyakowsky equation.
Polar
Non-polar
Both (A) & (B)
Neither (A) nor (B)
Lowering of condenser temperature (keeping the evaporator temperature constant) in case of vapour compression refrigeration system results in
Increased COP
Same COP
Decreased COP
Increased or decreased COP; depending upon the type of refrigerant
For a real gas, the chemical potential is given by
RT d ln P
RT d ln f
R d ln f
None of these
For an ideal liquid solution, which of the following is unity?
Activity
Fugacity
Activity co-efficient
Fugacity co-efficient
Equilibrium constant decreases as the temperature
Increases, for an exothermic reaction
Decreases, for an exothermic reaction
Increases, for an endothermic reaction
None of these
Joule-Thomson experiment is
Isobaric
Adiabatic
Isenthalpic
Both (B) & (C)
In case of a reversible process (following pvn = constant), work obtained for trebling the volume (v1 = 1 m3 and v23 m3) is maximum, when the value of 'n' is
0
1
y = 1.44
1.66
For an ideal gas, the internal energy depends upon its __________ only.
Molecular size
Temperature
Volume
Pressure
For an ideal gas, the enthalpy
Increases with rise in pressure
Decreases with rise in pressure
Is independent of pressure
Is a path function
A solute distributes itself between two nonmiscible solvents in contact with each other in such a way that, at a constant temperature, the ratio of its concentrations in two layers is constant, irrespective of its total amount. This is
The distribution law
Followed from Margules equation
A corollary of Henry's law
None of these
Entropy change of the reaction, H2O (liquid) → H2O (gas), is termed as the enthalpy of
Solution
Vaporisation
Formation
Sublimation
As pressure approaches zero, the ratio of fugacity to pressure (f/P) for a gas approaches
Zero
Unity
Infinity
An indeterminate value
Gibbs free energy per mole for a pure substance is equal to the
Latent heat of vaporisation
Chemical potential
Molal boiling point
Heat capacity
What is the value of Joule-Thomson co-efficient for an ideal gas?
+ve
-ve
0
∞
In case of an __________ process, the temperature of the system increases.
Isothermal compression
Isothermal expansion
Adiabatic expansion
Adiabatic compression
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
In a reversible process
Tds = dE + dW
dE - dW = Tds
dW - dE = Tds
Tds - dW + dE >0
Maximum work that could be secured by expanding the gas over a given pressure range is the __________ work.
Isothermal
Adiabatic
Isentropic
None of these
Which of the following liquid metals has the highest thermal conductivity?
Molten sodium
Molten lead
Mercury
Molten potassium
The unit of equilibrium constant of a chemical reaction is the same as that of
Molar concentration
Temperature
Internal energy
None of these
The equation DU = Tds - PdV is applicable to infinitesimal changes occuring in
An open system of constant composition
A closed system of constant composition
An open system with changes in composition
A closed system with changes in composition
COP of a refrigerator drawing 1 kW of power per ton of refrigeration is about
0.5
3.5
4.5
8.5
As the entropy of the universe is increasing, day by day, the work producing capacity of a heat engine is
Not changed
Decreasing
Increasing
Data sufficient, can't be predicted
Free energy, fugacity and activity co-efficient are all affected by change in the temperature. The fugacity co-efficient of a gas at constant pressure ____with the increase of reduced temperature.
Decreases
Increases
Remains constant
Decreases logarithmically