A gas shows deviation from ideal behaviour at
A. Low pressure and high temperature
B. Low pressure and low temperature
C. Low temperature and high pressure
D. High temperature and high pressure
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Fugacity and pressure are numerically not equal for the gases
A. At low temperature and high pressure
B. At standard state
C. Both A and B
D. In ideal state
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__________ equation predicts the activity co-efficient from experimental data.
A. Lewis-Randall
B. Margules
C. Van Laar
D. Both B & C
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Pick out the correct statement.
A. If an insoluble gas is passed through a volatile liquid placed in a perfectly insulated container, the temperature of the liquid will increase
B. A process is irreversible as long as Δ S for the system is greater than zero
C. The mechanical work done by a system is always equal to ∫P.dV
D. The heat of formation of a compound is defined as the heat of reaction leading to the formation of the compound from its reactants
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Entropy change of mixing two liquid substances depends upon the
A. Molar concentration
B. Quantity (i.e. number of moles)
C. Both A and B
D. Neither A nor B
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Pick out the wrong statement.
A. Surface tension of a substance vanishes at critical point, as there is no distinction between liquid and vapour phases at its critical point
B. Entropy of a system decreases with the evolution of heat
C. Change of internal energy is negative for exothermic reactions
D. The accentric factor for all materials is always more than one
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Ideal gas law is applicable at
A. Low T, low P
B. High T, high P
C. Low T, high P
D. High T, low P
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Ideal refrigeration cycle is
A. Same as Carnot cycle
B. Same as reverse Carnot cycle
C. Dependent on the refrigerant's properties
D. The least efficient of all refrigeration processes
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Specific volume of an ideal gas is
A. Equal to its density
B. The reciprocal of its density
C. Proportional to pressure
D. None of these
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The necessary and sufficient condition for equilibrium between two phases is
A. The concentration of each component should be same in the two phases
B. The temperature of each phase should be same
C. The pressure should be same in the two phases
D. The chemical potential of each component should be same in the two phases
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In case of a reversible process (following pvn = constant), work obtained for trebling the volume (v1 = 1 m3 and v2 = 3 m3 ) is maximum, when the value of 'n' is
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In an adiabatic process, the
A. Heat transfer is zero
B. Temperature change is zero
C. Work done is a path function
D. Enthalpy remains constant
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Which of the following is not an extensive property?
A. Free energy
B. Entropy
C. Refractive index
D. None of these
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In an irreversible process
A. Tds = dE - dW = 0
B. DE - dW - Tds = 0
C. Tds - dE + dW< 0
D. Tds - dT + dW< 0
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In any spontaneous process,
A. Only F decreases
B. Only A decreases
C. Both F and A decreases
D. Both F and A increase
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The enthalpy change when ammonia gas is dissolved in water is called the heat of
A. Solution
B. Formation
C. Dilution
D. Combustion
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During adiabatic expansion of gas
A. Pressure remains constant
B. Pressure is increased
C. Temperature remains constant
D. None of these
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Compound having large heat of formation is
A. More stable
B. Less stable
C. Not at all stable (like nascent O2 )
D. Either more or less stable; depends on the compound
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The equation DU = Tds - PdV is applicable to infinitesimal changes occuring in
A. An open system of constant composition
B. A closed system of constant composition
C. An open system with changes in composition
D. A closed system with changes in composition
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Pick out the correct statement.
A. Compression ratio of an Otto engine is comparatively higher than a diesel engine
B. Efficiency of an Otto engine is higher than that of a diesel engine for the same compression ratio
C. Otto engine efficiency decreases with the rise in compression ratio, due to decrease in work produced per quantity of heat
D. Diesel engine normally operates at lower compression ratio than an Otto engine for an equal output of work
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