Work done is a
Property of the system
Path function
Point function
State description of a system
Correct Answer :
B. Path function
Related Questions
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
The value of Joule-Thomson co-efficient, in case where cooling occurs after the throttling process is
0
∞
+ve
-ve
During the phase transition, __________ changes.
Pressure
Volume
Temperature
All (A), (B) and (C)
The first law of thermodynamics is a statement of conservation of
Heat
Momentum
Energy
Work
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
Maximum work that could be secured by expanding the gas over a given pressure range is the __________ work.
Isothermal
Adiabatic
Isentropic
None of these
For an ideal gas, the enthalpy
Increases with rise in pressure
Decreases with rise in pressure
Is independent of pressure
Is a path function
The first law of thermodynamics is a restatement of the law of conservation of
Mass
Energy
Momentum
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'
Joule-Thomson effect i.e., a throttling process is a constant __________ process.
Entropy
Temperature
Internal energy
Enthalpy
Any substance above its critical temperature exists as
Saturated vapour
Solid
Gas
Liquid
To obtain integrated form of Clausius-Clapeyron equation, ln (P2/P1) = (ΔHV/R) (1/T1 - 1/T2) from the exact Clapeyron equation, it is assumed that the
Volume of the liquid phase is negligible compared to that of vapour phase
Vapour phase behaves as an ideal gas
Heat of vaporisation is independent of temperature
All (A), (B) & (C)
A gas has a volume of 27.3 c.c. at 0°C. Its volume at 10°C (if pressure remains unchanged) will be __________ c.c.
2.73
28.3
273
283
Entropy of the system decreases, when
Snow melts into water
A gas expands spontaneously from high pressure to low pressure
Water is converted into ice
Both (B) & (C)
In jet refrigerators, the refrigerating fluid is practically always
Water
Ammonia
Freon
Brine
Which of the following units is not present in both the vapor compression refrigeration system and absorption refrigeration system?
Expansion valve
Condenser
Refrigerator
Compressor
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
The expression for entropy change, ΔS = n Cp . ln (T2/T1), is valid for the __________ of a substance.
Simultaneous pressure & temperature change
Heating
Cooling
Both (B) and (C)
The acentric factor of a materical, 'ω', is defined as ω = -log10(Prsat)Tr-1 = 0.7, where, Prsat = reduced vapor pressure, Tr = reduced temperature. The value of acentric factor is always
> 2
< 1
> 1
< 3
Pick out the wrong statement.
The conversion for a gas phase reaction increases with decrease in pressure, if there is an increase in volume accompanying the reaction
With increase in temperature, the equilibrium constant increases for an exothermic reaction
The equilibrium constant of a reaction depends upon temperature only
The conversion for a gas phase reaction increases with increase in pressure, if there is a decrease in volume accompanying the reaction
The molar excess Gibbs free energy, gE, for a binary liquid mixture at T and P is given by, (gE/RT) = A . x1. x2, where A is a constant. The corresponding equation for ln y1, where y1 is the activity co-efficient of component 1, is
A . x22
Ax1
Ax2
Ax12
In the decomposition of PCl5 represented by, PCl5 PCl3 + Cl2, decrease in the pressure of the system will __________ the degree of dissociation of PCl5.
Increase
Decrease
Not alter
None of these
Pick out the wrong statement.
The values of (∂P/∂V)T and (∂2P/∂V2)T are zero for a real gas at its critical point
Heat transferred is equal to the change in the enthalpy of the system, for a constant pressure, non-flow, mechanically reversible process
Thermal efficiency of a Carnot engine depends upon the properties of the working fluid besides the source & sink temperatures
During a reversible adiabatic process, the entropy of a substance remains constant
The principle applied in liquefaction of gases is
Adiabatic expansion
Joule-Thomson effect
Both (A) and (B)
Neither (A) nor (B)
The temperature at which a real gas obeys the ideal gas laws over a wide range of pressure is called __________ temperature.
Boyle
Inversion
Critical
Reduced
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)
The standard Gibbs free energy change of a reaction depends on the equilibrium
Pressure
Temperature
Composition
All (A), (B) and (C)
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
Critical solution temperature (or the consolute temperature) for partially miscible liquids (e.g., phenol-water) is the minimum temperature at which
A homogeneous solution (say of phenol water) is formed
Mutual solubility of the two liquids shows a decreasing trend
Two liquids are completely separated into two layers
None of these