Claude gas liquefaction process employs cooling
At constant pressure
By throttling
By expansion in an engine
None of these
Correct Answer :
C. By expansion in an engine
Related Questions
At __________ point, all the three phases (i.e. solid, liquid and gas) co-exist.
Eutectic
Triple
Plait
Critical
In the equation, PVn = Constant, if the value of n = 0, then it represents a reversible __________ process.
Isobaric
Isothermal
Isentropic
Isometric
Isotherm on an enthalpy-concentration diagram, for an ideal solution will be a
Straight line
Sine curve
Parabola
Hyperbola
Vapour which is at a pressure smaller than the saturation pressure for the temperature involved is called a __________ vapour.
Superheated
Desuperheated
Non-condensable
None of these
Equilibrium constant of a reaction varies with the
Initial concentration of the reactant
Pressure
Temperature
None of these
For a given substance at a specified temperature, activity is __________ to fugacity.
Directly proportional
Inversely proportional
Equal
None of these
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
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
__________ calorimeter is normally used for measuring the dryness fraction of steam, when it is very low.
Bucket
Throttling
Separating
A combination of separating & throttling
Internal energy change of a system over one complete cycle in a cyclic process is
Zero
+ve
-ve
Dependent on the path
The point at which all the three (solid, liquid and gas) phases co-exist, is known as the __________ point.
Freezing
Triple
Boiling
Boyle
The equation Tds = dE - PdV applies to
Single phase fluid of varying composition
Single phase fluid of constant composition
Open as well as closed systems
Both (B) and (C)
Melting of wax is accompanied with __________ in entropy.
Increase
Decrease
No change
None of these
Entropy change for an irreversible process taking system and surrounding together is
0
> 0
< 0
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
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
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
The expression for entropy change given by, ΔS = nR ln (V2/V1) + nCv ln (T2/T1) is valid for
Reversible isothermal volume change
Heating of a substance
Cooling of a substance
Simultaneous heating and expansion of an ideal gas
On a P-V diagram of an ideal gas, suppose a reversible adiabatic line intersects a reversible isothermal line at point A. Then at a point A, the slope of the reversible adiabatic line (∂P/∂V)s and the slope of the reversible isothermal line (∂P/ ∂V)T are related as (where, y = Cp/Cv)
(∂P/∂V)S = (∂P/∂V)T
(∂P/∂V)S = [(∂P/∂V)T]Y
(∂P/∂V)S = y(∂P/∂V)T
(∂P/∂V)S = 1/y(∂P/∂V)T
Fundamental principle of refrigeration is based on the __________ law of thermodynamics.
Zeroth
First
Second
Third
A refrigeration cycle is the same as a __________ cycle,
Turbine
Heat engine
Reversed heat engine
None of these
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
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
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
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)
Which of the following is Virial equation of state?
(p + a/V2)(V - b) = nRT
PV = nRT
PV = A + B/V + C/V2 + D/V3 + ...
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
Gases are cooled in Joule-Thomson expansion, when it is __________ inversion temperature.
Below
At
Above
Either 'b' or 'c'
PVy = constant, holds good for an isentropic process, which is
Reversible and isothermal
Isothermal and irreversible
Reversible and adiabatic
Adiabatic and irreversible
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