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4

The third law of thermodynamics states that the

A. Heat capacity of a crystalline solid is zero at absolute zero temperature

B. Heat transfer from low temperature to high temperature source is not possible without external work

C. Gases having same reduced properties behaves similarly

D. None of these

Correct Answer :

A. Heat capacity of a crystalline solid is zero at absolute zero temperature


Related Questions

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With increase in temperature, the atomic heat capacities of all solid elements

A. Increases

B. Decreases

C. Remains unchanged

D. Decreases linearly

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The adiabatic throttling process of a perfect gas is one of constant enthalpy

A. In which there is a temperature drop

B. Which is exemplified by a non-steady flow expansion

C. Which can be performed in a pipe with a constriction

D. In which there is an increase in temperature

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4

What is the degree of freedom for a system comprising liquid water equilibrium with its vapour?

A. 0

B. 1

C. 2

D. 3

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4

If the vapour pressure at two temperatures of a solid phase in equilibrium with its liquid phase are known, then the latent heat of fusion can be calculated by the

A. Maxwell's equation

B. Clausius-Clapeyron Equation

C. Van Laar equation

D. Nernst Heat Theorem

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4

Number of phases in a colloidal system is:

A. 1

B. 2

C. 3

D. 4

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4

Chemical potential (an intensive property) of a substance is a force that drives the chemical system to equilibrium and is equal to its partial molar properties. The ratio of chemical potential to free energy of a pure substance at constant temperature and pressure is

A. 0

B. 1

C.

D. None of these

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4

For a single component two phase mixture, the number of independent variable properties are

A. Two

B. One

C. Zero

D. Three

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4

Gibbs phase rule finds application, when heat transfer occurs by

A. Conduction

B. Convection

C. Radiation

D. Condensation

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4

What happens in a reversible adiabatic expansion process?

A. Heating takes place

B. Cooling takes place

C. Pressure is constant

D. Temperature is constant

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4

Entropy change for an irreversible isolated system is

A.

B. 0

C. < 0

D. > 0

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4

Claude gas liquefaction process employs cooling

A. At constant pressure

B. By throttling

C. By expansion in an engine

D. None of these

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4

The expression, ΔG = nRT. ln(P2/P1), gives the free energy change

A. With pressure changes at constant temperature

B. Under reversible isothermal volume change

C. During heating of an ideal gas

D. During cooling of an ideal gas

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4

In the equation, PVn = constant, if the value of n is in between 1 and y (i.e. Cp/Cv), then it represents a reversible __________ process.

A. Isometric

B. Polytropic

C. Isentropic

D. Isobaric

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4

Pick out the correct statement.

A. Entropy and enthalpy are path functions

B. In a closed system, the energy can be exchanged with the surrounding, while matter cannot be exchanged

C. All the natural processes are reversible in nature

D. Work is a state function

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A system is said to be isopiestic, if there is no __________ change.

A. Temperature

B. Pressure

C. Volume

D. None of these

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4

Out of the following refrigeration cycles, which one has the minimum COP (Co-efficient of performance)?

A. Air cycle

B. Carnot cycle

C. Ordinary vapour compression cycle

D. Vapour compression with a reversible expansion engine

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4

As the entropy of the universe is increasing, day by day, the work producing capacity of a heat engine is

A. Not changed

B. Decreasing

C. Increasing

D. Data sufficient, can't be predicted

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4

Boyle's law for gases states that

A. P ∝ 1/V, when temperature is constant

B. P ∝ 1/V, when temperature & mass of the gas remain constant

C. P ∝ V, at constant temperature & mass of the gas

D. P/V = constant, for any gas

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4

The melting point of paraffin wax (which contracts on solidification) __________ with pressure rise.

A. Increases

B. Decreases

C. Remains unchanged

D. Decreases linearly

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Sublimation temperature of dry ice (solid CO2) is __________ °C.

A. -273

B. 0

C. -78

D. 5

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4

In a reversible process

A. Tds = dE + dW

B. dE - dW = Tds

C. dW - dE = Tds

D. Tds - dW + dE >0

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4

The following heat engine produces power of 100,000 kW. The heat engine operates between 800 K and 300 K. It has a thermal efficiency equal to 50% of that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is

A. 100,000 kW

B. 160,000 kW

C. 200,000 kW

D. 320,000 kW

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4

For an incompressible fluid, the __________ is a function of both pressure as well as temperature.

A. Internal energy

B. Enthalpy

C. Entropy

D. All (A), (B) & (C)

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4

For a reversible process involving only pressure-volume work

A. (dF)T, p < 0

B. (dF)T, p > 0

C. (dF)T, p = 0

D. (dA)T, v < 0

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4

Number of components (C), phase (P) and degrees of freedom (F) are related by Gibbs phase rule as

A. P + F - C = 2

B. C = P - F + 2

C. F = C - P - 2

D. P = F - C - 2

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4

Compressibility factor (i.e., the ratio of actual volume of gas to the volume predicted by ideal gas law) for all gases are

A. Always greater than one

B. Same at the same reduced temperature

C. Same at the same reduced pressure

D. Both (B) & (C)

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The unit of fugacity is the same as that of the

A. Pressure

B. Temperature

C. Volume

D. Molar concentration

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The minimum number of phases that can exist in a system is

A. 0

B. 1

C. 2

D. 3

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Lowering of condenser temperature (keeping the evaporator temperature constant) in case of vapour compression refrigeration system results in

A. Increased COP

B. Same COP

C. Decreased COP

D. Increased or decreased COP; depending upon the type of refrigerant

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4

The ammonia synthesis reaction represented by N2 + 3H2 2NH3; ΔH = - 22.4 kcal, is

A. Endothermic

B. Exothermic

C. Isothermal

D. Adiabatic