4

# During Joule-Thomson expansion of gases

Enthalpy remains constant

Entropy remains constant

Temperature remains constant

None of these

A. Enthalpy remains constant

4

# Free energy changes for two reaction mechanism 'X' and 'Y are respectively - 15 and - 5 units. It implies that X is

Slower than Y

Faster than Y

Three times slower than Y

Three times faster than Y

4

Infinity

Unity

Constant

Negative

4

# In vapour compression refrigeration system, if the evaporator temperature and the condenser temperatures are -13°C and 37°C respectively, the Carnot COP will be

5.2

6.2

0.168

Data insufficient, can't be found out

4

Isometric

Polytropic

Isentropic

Isobaric

4

Entropy

Temperature

Enthalpy

Pressure

4

# The Carnot co-efficient of performance (COP) of a domestic air conditioner compared to a household refrigerator is

Less

More

Same

Dependent on climatic conditions

4

# A gas can be liquefied by pressure alone only, when its temperature is __________ its critical temperature.

Less than

More than

Equal to or higher than

Less than or equal to

4

0

1

2

3

4

# A refrigeration cycle is the same as a __________ cycle,

Turbine

Heat engine

Reversed heat engine

None of these

4

# The third law of thermodynamics states that the

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

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

Gases having same reduced properties behaves similarly

None of these

4

# 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

Lewis-Randall rule

Statement of Van't Hoff Equation

Le-Chatelier's principle

None of these

4

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

Increases

Decreases

Remain constant

Increases linearly

4

# Ideal refrigeration cycle is

Same as Carnot cycle

Same as reverse Carnot cycle

Dependent on the refrigerant's properties

The least efficient of all refrigeration processes

4

# A Carnot cycle consists of the following steps:

Two isothermal and two isentropic

Two isobaric and two isothermal

Two isochoric and two isobaric

Two isothermals and two isochoric

4

Increase

Decrease

Not alter

None of these

4

3

2

1

0

4

# Solid and liquid phases of a substance are in equilibrium at the

Critical temperature

Melting point

Freezing point

Both (B) and (C)

4

50 kcal/hr

200 BTU/hr

200 BTU/minute

200 BTU/day

4

Eutectic

Triple

Plait

Critical

4

P1ACBP2P1

ACBB1A1A

ACBDA

4

0.25

0.5

0.75

1

4

0

< 0

< 1

> 1

4

Ideal

Real

Isotonic

None of these

4

# The thermodynamic law, PVy = constant, is not applicable in case of

Ideal compression of air

Free expansion of an ideal gas

Adiabatic expansion of steam in a turbine

Adiabatic compression of a perfect gas

4

# Which of the following is not a unit of the equilibrium constant Kp? (where, Δx = number of moles of products number of moles of reactants)

(atm)Δx, when Δx is negative

(atm)Δx, when Δx is positive

Dimensionless, when Δx = 0

(atm)Δx2, when Δx > 0

4

Isothermal

Isentropic

None of these

4

Saturated vapour

Solid

Gas

Liquid

4

# The expression, nRT ln(P1/P2), is for the __________of an ideal gas.

Compressibility

Work done under isothermal condition

Co-efficient of thermal expansion

4

# Chemical potential is a/an

Extensive property

Intensive property

Force which drives the chemical system to equilibrium

Both (B) and (C)