০০। "At the absolute zero temperature, the entropy of every perfectly crystalline substance becomes zero". This follows from the
ক) third law of thermodynamics
খ) second law of thermodynamics
গ) Nernst heat theorem
ঘ) Maxwell's relations
০১। "Dry ice" is
ক) moisture free ice
খ) solid helium
গ) solid carbon dioxide
ঘ) none of these
০২। "If different processes are used to bring about the same chemical reaction, the enthalpy change is same for all of them". This is __________ law.
ক) Hess's
খ) Kirchoff's
গ) Lavoisier and Laplace
ঘ) none of these
০৩। "Law of corresponding states" says that
ক) , two different gases behave similarly, if their reduced properties (i.e. P, V and T) are same.
খ) the surface of separation (i. e. the meniscus) between liquid and vapour phase disappears at the critical temperature.
গ) no gas can be liquified above the critical temperature, howsoever high the pressure may be.
ঘ) the molar heat of energy of gas at constant volume should be nearly constant (about 3 calories).
০৪। "The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances". This is the
ক) Lewis-Randall rule.
খ) statement of Vant-Hoff equation.
গ) Le-Chatelier's principle.
ঘ) none of these.
০৫। "When a gas is expanded from high pressure region to low pressure region ; temper -ature change occurs". This phenomenon is related to the
ক) Gibbs-Duhem equation
খ) Gibbs-Helmholtz equation
গ) Third law of thermodynamics
ঘ) Joule-Thomson effect
০৬। "When a system in equilibrium is subjected to a change in temperature, pressure or concentration, the equilibrium is displaced in a direction which tends to undo the effect of the change." This is called the
ক) Le-Chatelier principle.
খ) Kopp's rule.
গ) law of corresponding state.
ঘ) Arrehenius hypothesis.
০৭। 'The fugacity of a gas in a mixture is equal to the product of its mole fraction and its fugacity in the pure state at the total pressure of the mixture". This is
ক) the statement as per Gibbs-Helmholtz
খ) called Lewis-Randall rule
গ) Henry's law
ঘ) none of these
০৮। 1m3 of an ideal gas at 500 K and 1000 kPa expands reversibly to 5 times its initial volume in an insulated container. If the specific heat capacity (at constant pressure) of the gas is 21 J/mole . K, the final temperature will be
ক) 35 K
খ) 174 K
গ) 274 K
ঘ) 154 K
০৯। 1st law of thermodynamics is nothing but the law of conservation of
ক) momentum
খ) mass
গ) energy
ঘ) none of these
১০। 4 kg moles of an ideal gas expands in vacuum spontaneously. The work done is
ক) 4 J
খ) ∞
গ) 0
ঘ) 8 J
১১। A Carnot cycle consists of the following steps :
ক) Two isothermals and two isentropics.
খ) Two isobarics and two isothermals.
গ) Two isochorics and two isobarics.
ঘ) Two isothermals and two isochorics.
১২। A change in state involving a decrease in entropy can be spontaneous, only if
ক) it is exothermic.
খ) it is isenthalpic.
গ) it takes place isothermally.
ঘ) it takes place at constant volume.
১৩। A chemical reaction will occur spontaneously at constant pressure and temperature, if the free energy is
ক) zero
খ) positive
গ) negative
ঘ) none of these
১৪। A closed system is cooled reversibly from 100°C to 50°C. If no work is done on the system
ক) its internal energy (U) decreases and its entropy (S) increases.
খ) U and S both decreases
গ) U decreases but S is constant.
ঘ) U is constant but S decreases.
১৫। A cyclic engine exchanges heat with two reservoirs maintained at 100 and 300°C respectively. The maximum work (in J) that can be obtained from 1000 J of heat extracted from the hot reservoir is
ক) 349
খ) 651
গ) 667
ঘ) 1000
১৬। 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.
ক) 448
খ) 224
গ) 22.4
ঘ) data insufficient; can't be computed
১৭। A domestic refrigerator has a/an __________ cooled condenser.
ক) water
খ) air
গ) evaporative
ঘ) gas
১৮। A gas can be liquified by pressure alone only, when its temperature is __________ its critical temperature.
ক) less than
খ) more than
গ) equal to or higher than
ঘ) less than or equal to
১৯। 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.