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4

(∂H/∂T)P is the mathematical expression for

A. CV

B. Entropy change

C. Gibbs free energy

D. None of these

Correct Answer :

D. None of these


Related Questions

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4

Equilibrium constant of a reaction varies with the

A. Initial concentration of the reactant

B. Pressure

C. Temperature

D. None of these

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4

Throttling process is a/an __________ process.

A. Reversible and isothermal

B. Irreversible and constant enthalpy

C. Reversible and constant entropy

D. Reversible and constant enthalpy

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4

A refrigerator may be termed as a

A. Heat pump

B. Heat engine

C. Carnot engine

D. None of these

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4

In Joule-Thomson porous plug experiment, the

A. Enthalpy does not remain constant

B. Entire apparatus is exposed to surroundings

C. Temperature remains constant

D. None of these

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4

If different processes are used to bring about the same chemical reaction, the enthalpy change is same for all of them. This is __________ law.

A. Hess's

B. Kirchoff's

C. Lavoisier and Laplace

D. None of these

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4

In the decomposition of PCl5 represented by, PCl5 PCl3 + Cl2, decrease in the pressure of the system will __________ the degree of dissociation of PCl5.

A. Increase

B. Decrease

C. Not alter

D. None of these

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4

For an ideal gas, the activity co-efficient is

A. Directly proportional to pressure

B. Inversely proportional to pressure

C. Unity at all pressures

D. None of these

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4

Co-efficient of Performance (COP) of a refrigerator is the ratio of the

A. Work required to refrigeration obtained

B. Refrigeration obtained to the work required

C. Lower to higher temperature

D. Higher to lower temperature

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4

If heat contents of CH4, C2H4 and C3H8 are -17.9, 12.5 and -24.8 kcal/mole respectively, than ΔH for the reaction CH4(g) + C2H4(g) C3H8(g) will be __________ Kcal.

A. -19.4

B. -30.2

C. 55.2

D. -55.2

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4

Pick out the wrong statement.

A. Trouton's ratio of non-polar liquids is calculated using Kistyakowsky equation

B. Thermal efficiency of a Carnot engine is always less than 1

C. An equation relating pressure, volume and temperature of a gas is called ideal gas equation

D. None of these

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4

Dryness fraction of wet steam is defined as the ratio of mass of vapour in the mixture to the mass of mixture __________ calorimeter is not used for measuring the dryness fraction of steam.

A. Bomb

B. Separating

C. Bucket

D. Throttling

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4

After throttling, gas temperature

A. Decreases

B. Increases

C. Remain same

D. May increase or decrease; depends on the nature of the gas

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4

The change in Gibbs free energy for vaporisation of a pure substance is

A. Positive

B. Negative

C. Zero

D. May be positive or negative

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4

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.

A. 270

B. 327

C. 300

D. 540

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4

If the pressure on 100 c.c. of air is halved, then its volume (at the same temperature) would be __________ c.c.

A. 100

B. 50

C. 205

D. 200

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4

Claude's liquefaction process employs the cooling of gases by

A. Expansion in an engine

B. Following a constant pressure cycle

C. Throttling

D. None of these

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4

Which is a state function?

A. Specific volume

B. Work

C. Pressure

D. Temperature

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4

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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4

Entropy, which is a measure of the disorder of a system, is:

A. Independent of pressure

B. Independent of temperature

C. Zero at absolute zero temperature for a perfect crystalline substance

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

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4

Fundamental principle of refrigeration is based on the __________ law of thermodynamics.

A. Zeroth

B. First

C. Second

D. Third

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4

With increase in compression ratio, the efficiency of the otto engine

A. Increases

B. Decreases

C. Remain constant

D. Increases linearly

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4

Critical solution temperature (or the consolute temperature) for partially miscible liquids (e.g., phenol-water) is the minimum temperature at which

A. A homogeneous solution (say of phenol water) is formed

B. Mutual solubility of the two liquids shows a decreasing trend

C. Two liquids are completely separated into two layers

D. None of these

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4

Which of the following is not a common refrigerant?

A. Freon-12

B. Ethylene

C. Ammonia

D. Carbon dioxide

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4

Pick out the wrong statement

A. Phase rule variables are intensive properties

B. Heat and work are both state function

C. The work done by expansion of a gas in vacuum is zero

D. CP and CV are state function

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4

The co-efficient of performance (COP) of a refrigerating system, which is its index of performance, is defined as the ratio of useful refrigeration to the net work. The units of __________ and COP are the same.

A. Kinematic viscosity

B. Work

C. Temperature

D. None of these

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4

The temperature at which a real gas obeys the ideal gas laws over a wide range of pressure is called the __________ temperature.

A. Critical

B. Boyle

C. Inversion

D. Reduced

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4

On opening the door of an operating refrigerator kept in a closed room, the temperature of the room will

A. Increase

B. Decrease

C. Remain same

D. Increase in summer and will decrease in winter

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4

Pick out the wrong statement.

A. Activity co-efficient is dimensionless.

B. In case of an ideal gas, the fugacity is equal to its pressure.

C. In a mixture of ideal gases, the fugacity of a component is equal to the partial pressure of the component.

D. The fugacity co-efficient is zero for an ideal gas

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4

Number of degrees of freedom for a three phase system in equilibrium comprising of three nonreacting chemical species is

A. 2

B. 0

C. 1

D. 3

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4

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)

A. √(2KT/m)

B. √(3KT/m)

C. √(6KT/m)

D. 3KT/m