The equation, Cp - Cv = R, is true for __________ gas.
No
Any real
Only ideal
Both (B) and (C)
Correct Answer :
C. Only ideal
Related Questions
The first law of thermodynamics is a statement of conservation of
Heat
Momentum
Energy
Work
If an ideal solution is formed by mixing two pure liquids in any proportion, then the __________ of mixing is zero
Enthalpy
Volume
Both 'a' & 'b'
Neither 'a' nor 'b'
Which of the following is not an equation of state?
Bertholet equation
Clausius-Clapeyron equation
Beattie-Bridgeman equation
None of these
A/an __________ system is exemplified by a vessel containing a volatile liquid in contact with its vapor.
Isolated
Closed
Open
None of these
The temperature at the eutectic point of the system is the __________ temperature that can be attained in the system.
Lowest
Highest
Average
None of these
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
In an irreversible process
Tds = dE - dW = 0
dE - dW - Tds = 0
Tds - dE + dW < 0
Tds - dT + dW < 0
Which one is true for a throttling process?
A gas may have more than one inversion temperatures
The inversion temperature is different for different gases
The inversion temperature is same for all gases
The inversion temperature is the temperature at which Joule-Thomson co-efficient is infinity
The minimum number of phases that can exist in a system is
0
1
2
3
A cylinder contains 640 gm of liquid oxygen. The volume occupied (in litres) by the oxygen, when it is released and brought to standard conditions (0°C, 760 mm Hg) will be __________ litres.
448
224
22.4
Data insufficient; can't be computed
Entropy of an ideal gas depends upon its
Pressure
Temperature
Both (A) & (B)
Neither (A) nor (B)
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
The root mean square speed of molecules of a gas is equal to (where, m = mass of the molecule K = Boltzmanns constant, T = absolute temperature)
√(2KT/m)
√(3KT/m)
√(6KT/m)
3KT/m
As the temperature is lowered towards the absolute zero, the value of the quantity (∂ΔF/∂T) approaches
Zero
Unity
Infinity
None of these
Joule-Thomson experiment is
Isobaric
Adiabatic
Isenthalpic
Both (B) & (C)
A change in state involving a decrease in entropy can be spontaneous, only if
It is exothermic
It is isenthalpic
It takes place isothermally
It takes place at constant volume
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
For a thermodynamic system containing 'x' chemical species, the maximum number of phases that can co-exist at equilibrium is
x
x + 1
x + 2
x + 3
For a spontaneous process, free energy
Is zero
Increases
Decreases whereas the entropy increases
And entropy both decrease
Fugacity co-efficient of a substance is the ratio of its fugacity to
Mole fraction
Activity
Pressure
Activity co-efficient
The theoretical minimum work required to separate one mole of a liquid mixture at 1 atm, containing 50 mole % each of n- heptane and noctane into pure compounds each at 1 atm is
-2 RT ln 0.5
-RT ln 0.5
0.5 RT
2 RT
For an exothermic reaction
Only enthalpy change (ΔH) is negative
Only internal energy change (ΔE) is negative
Both ΔH and ΔE are negative
Enthalpy change is zero
In the reaction, C + O2 → CO2; ΔH = - 94 kcal. What is the heat content (enthalpy) of O2?
-94 kcal
> -94 kcal
< - 94 kcal
Zero
In the equation, PVn = constant, if the value of n = 1, then it represents a reversible __________ process.
Isothermal
Isobaric
Polytropic
Adiabatic
Pick out the wrong statement.
An ideal liquid or solid solution is defined as one in which each component obeys Raoult's law
If Raoult's law is applied to one component of a binary mixture; Henry's law or Raoult's law is applied to the other component also
Henry's law is rigorously correct in the limit of infinite dilution
None of these
Which is an example of closed system?
Air compressor
Liquid cooling system of an automobile
Boiler
None of these
Number of phases in a colloidal system is:
1
2
3
4
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
Heat pump
Accomplishes only space heating in winter
Accomplishes only space cooling in summer
Accomplishes both (A) and (B)
Works on Carnot cycle
A refrigeration cycle is a reversed heat engine. Which of the following has the maximum value of the co-efficient of performance (COP) for a given refrigeration effect?
Vapor compression cycle using expansion valve
Air refrigeration cycle
Vapor compression cycle using expansion engine
Carnot refrigeration cycle