The equation, PV = nRT, is best obeyed by gases at
Low pressure & high temperature
High pressure & low temperature
Low pressure & low temperature
None of these
Correct Answer :
A. Low pressure & high temperature
Related Questions
__________ Equation predicts the activity coefficient from experimental data.
Lewis-Randall
Margules
Van Laar
Both (B) & (C)
Helmholtz free energy (A) is defined as
A = H - TS
A = E - TS
A = H + TS
None of these
A two stage compressor is used to compress an ideal gas. The gas is cooled to the initial temperature after each stage. The intermediate pressure for the minimum total work requirement should be equal to the __________ mean of P1 and P2. (where, P1 and P2 are initial and final pressures respectively)
Logarithmic
Arithmetic
Geometric
Harmonic
For an isothermal process, the internal energy of a gas
Increases
Decreases
Remains unchanged
Data insufficient, can't be predicted
The energy of activation of exothermic reaction is
Zero
Negative
Very large compared to that for endothermic reaction
Not possible to predict
Pick out the correct statement.
Entropy and enthalpy are path functions
In a closed system, the energy can be exchanged with the surrounding, while matter cannot be exchanged
All the natural processes are reversible in nature
Work is a state function
Degree of freedom of the system ice-watervapour will be
0
1
2
3
What is the number of degrees of freedom for liquid water in equilibrium with a mixture of nitrogen and water vapor?
2
0
3
1
Which of the following is a thermodynamic property of a system?
Concentration
Mass
Temperature
Entropy
Which of the following is not an intensive property?
Volume
Density
Temperature
Pressure
The second law of thermodynamics states that
The energy change of a system undergoing any reversible process is zero
It is not possible to transfer heat from a lower temperature to a higher temperature
The total energy of system and surrounding remains the same
None of the above
Entropy of a substance remains constant during a/an __________ change.
Reversible isothermal
Irreversible isothermal
Reversible adiabatic
None of these
Throttling (Joule-Thomson effect) process is a constant __________ process.
Enthalpy
Entropy
Pressure
None of these
Cv for an ideal gas
Does not depend upon temperature
Is independent of pressure only
Is independent of volume only
Is independent of both pressure and volume
A solid is transformed into vapour without going to the liquid phase at
Triple point
Boiling point
Below triple point
Always
In reactions involving solids and liquids (where change in volume is negligible), the heat of reaction at constant pressure as compared to that at constant volume is
More
Less
Same
Unpredictable; depends on the particular reaction
Gibbs free energy at constant pressure and temperature under equilibrium conditions is
∞
0
Maximum
Minimum
An isentropic process is carried out at constant
Volume
Pressure
Temperature
All (A), (B) and (C)
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)
Work done may be calculated by the expression ∫ p dA for __________ processes.
Non-flow reversible
Adiabatic
Both (A) and (B)
Neither (A) nor (B)
Which of the following is affected by the temperature?
Fugacity
Activity co-efficient
Free energy
All (A), (B) & (C)
Melting of ice exemplifies a/an
Adiabatic process
Endothermic reaction
Exothermic reaction
Process involving a chemical reaction
Entropy, which is a measure of the disorder of a system, is:
Independent of pressure
Independent of temperature
Zero at absolute zero temperature for a perfect crystalline substance
All (A), (B) & (C)
Work done in an adiabatic process between two states depends on the
Rate of heat transmission
Initial state only
End states only
None of these
Those solutions in which there is no volume change upon mixing the components in the liquid state and which, when diluted do not undergo any heat change (i.e. heat of dilution is zero), are called __________ solutions.
Ideal
Real
Isotonic
None of these
What is the ratio of adiabatic compressibility to isothermal compressibility?
1
< 1
> 1
>> 1
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
For equilibrium process (i.e. reversible) in an isolated system
ds = 0
ds < 0
ds > 0
ds = Constant
With increase in compression ratio, the efficiency of the otto engine
Increases
Decreases
Remain constant
Increases linearly
Entropy change of mixing two liquid substances depends upon the
Molar concentration
Quantity (i.e. number of moles)
Both (A) and (B)
Neither (A) nor (B)