The chemical potential for a pure substance is __________ its partial molal free energy.
More than
Less than
Equal to
Not related to
Correct Answer :
C. Equal to
Related Questions
A large iceberg melts at the base, but not at the top, because of the reason that
Ice at the base contains impurities which lowers its melting point
Due to the high pressure at the base, its melting point reduces
The iceberg remains in a warmer condition at the base
All (A), (B) and (C)
Fugacity and pressure are numerically equal, when the gas is
In standard state
At high pressure
At low temperature
In ideal state
The value of Joule-Thomson co-efficient, in case where cooling occurs after the throttling process is
0
∞
+ve
-ve
Pick out the wrong statement.
At constant pressure, solubility of a gas in a liquid diminishes with rise in temperature
Normally, the gases which are easily liquefied are more soluble in common solvents
The gases which are capable of forming ions in aqueous solution are much more soluble in water than in other solvents
At constant pressure, solubility of a gas in a liquid increases with rise in temperature
For a constant pressure reversible process, the enthalpy change (ΔH) of the system is
Cv.dT
Cp.dT
∫ Cp.dT
∫ Cv.dT
Which of the following identities can be most easily used to verify steam table data for superheated steam?
(∂T/∂V)S = (∂p/∂S)V
(∂T/∂P)S = (∂V/∂S)P
(∂P/∂T)V = (∂S/∂V)T
(∂V/∂T)P = -(∂S/∂P)T
The intensive properties are
Molar volume, density, viscosity and boiling point
Refractive index and surface tension
Both (A) and (B)
None of these
First law of thermodynamics deals with the
Direction of energy transfer
Reversible processes only
Irreversible processes only
None of these
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
Mollier chart is a __________ plot.
Pressure vs. enthalpy
Pressure vs. volume
Enthalpy vs. entropy
Temperature vs. entropy
For the reversible exothermic reaction, N2 + 3H2 2NH3, increase of pressure would
Shift the equilibrium towards right
Give higher yield of NH3
Both (B) and (C)
Neither (A) nor (B)
Pick out the correct statement:
In an isothermal system, irreversible work is more than reversible work
Under reversible conditions, the adiabatic work is less than isothermal work
Heat, work, enthalpy and entropy are all 'state functions'
Matter and energy cannot be exchanged with the surroundings in a closed system
Which is an example of closed system?
Air compressor
Liquid cooling system of an automobile
Boiler
None of these
Pressure-enthalpy chart is useful in refrigeration. The change in internal energy of an ideal fluid used in ideal refrigeration cycle is
Positive
Negative
Zero
Infinity
In the equation, PVn = constant, if the value of n is in between 1 and y (i.e. Cp/Cv), then it represents a reversible __________ process.
Isometric
Polytropic
Isentropic
Isobaric
At normal boiling point, molar entropy of vaporisation is __________ Joule/K°.mole.
72
92
142
192
Choose the condition that must be specified in order to liquify CO2 (triple point for CO2 is - 57°C and 5.2 atm).
Pressure must be kept below 5.2 atm
Temperature must be kept above - 57°C
Pressure must be kept below 5.2 atm. and temperature must be kept above 57°C
Pressure and temperature must be kept below 5.2 atm. and - 57°C respectively
Which of the following is not an intensive property?
Volume
Density
Temperature
Pressure
The partial molar enthalpy of a component in an ideal binary gas mixture of composition Z, at a temperature T and pressure P, is a function only of
T
T and P
T, P and Z
T and Z
Which of the following non-flow reversible compression processes require maximum work?
Adiabatic process
Isothermal process
Isobaric process
All require same work
Gases are cooled in Joule-Thomson expansion, when it is __________ inversion temperature.
Below
At
Above
Either 'b' or 'c'
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)
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
For organic compounds, group contribution method can be used for the estimation of
Critical properties
Specific gravity
Specific volume
Thermal conductivity
Sublimation temperature of dry ice (solid CO2) is __________ °C.
-273
0
-78
5
Work done is a
Property of the system
Path function
Point function
State description of a system
Melting of wax is accompanied with __________ in entropy.
Increase
Decrease
No change
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
What is the ratio of adiabatic compressibility to isothermal compressibility?
1
< 1
> 1
>> 1
Efficiency of a heat engine working on Carnot cycle between two temperature levels depends upon the
Two temperatures only
Pressure of working fluid
Mass of the working fluid
Mass and pressure both of the working fluid