4

# Which of the following has the minimum value of COP for a given refrigeration effect?

Reverse Carnot cycle

Ordinary vapour-compression cycle

Vapour-compression process with a reversible expansion engine

Air refrigeration cycle

D. Air refrigeration cycle

4

Reversible

Irreversible

Isothermal

4

Water

Air

Evaporative

Gas

4

# As pressure approaches zero, the ratio of fugacity to pressure (f/P) for a gas approaches

Zero

Unity

Infinity

An indeterminate value

4

# Which of the following is not an equation of state?

Bertholet equation

Clausius-Clapeyron equation

Beattie-Bridgeman equation

None of these

4

0

1

y = 1.44

1.66

4

# Forward reaction will be favoured for the exothermic reaction, represented by CO + H2O CO2 + H2, by

Low temperature and high pressure

Low temperature and low pressure

High temperature and high pressure

High temperature and low pressure

4

# High pressure steam is expanded adiabatically and reversibly through a well insulated turbine, which produces some shaft work. If the enthalpy change and entropy change across the turbine are represented by ΔH and ΔS respectively for this process:

Δ H = 0 and ΔS = 0

Δ H ≠ 0 and ΔS = 0

Δ H ≠ 0 and ΔS ≠ 0

Δ H = 0 and ΔS ≠ 0

4

# The unit of equilibrium constant of a chemical reaction is the same as that of

Molar concentration

Temperature

Internal energy

None of these

4

# Entropy of the system decreases, when

Snow melts into water

A gas expands spontaneously from high pressure to low pressure

Water is converted into ice

Both (B) & (C)

4

100,000 kW

160,000 kW

200,000 kW

320,000 kW

4

# During Joule-Thomson expansion of gases

Enthalpy remains constant

Entropy remains constant

Temperature remains constant

None of these

4

Positive

Negative

Zero

Infinity

4

# Cp - Cv = R is valid for __________ gases.

Ideal

Very high pressure

Very low temperature

All of the above

4

# Cv for an ideal gas

Does not depend upon temperature

Is independent of pressure only

Is independent of volume only

Is independent of both pressure and volume

4

# Reduced pressure of a gas is the ratio of its

Pressure to critical pressure

Critical pressure to pressure

Pressure to pseudocritical pressure

Pseudocritical pressure to pressure

4

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

In which there is a temperature drop

Which is exemplified by a non-steady flow expansion

Which can be performed in a pipe with a constriction

In which there is an increase in temperature

4

# Specific __________ does not change during a phase change (e.g. sublimation, melting, vaporisation etc.).

Entropy

Internal energy

Enthalpy

Gibbs free energy

4

0

1

< 1

> 1

4

0

> 0

< 0

None of these

4

# 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

Le-Chatelier principle

Kopp's rule

Law of corresponding state

Arrhenius hypothesis

4

Entropy

Temperature

Internal energy

Enthalpy

4

# The most important application of distribution law is in

Evaporation

Liquid extraction

Drying

Distillation

4

# The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is

Less pronounced

More pronounced

Equal

Data insufficient, can't be predicted

4

Two

One

Zero

Three

4

0

+ve

-ve

4

Equilibrium

4

# When liquid and vapour phases of one component system are in equilibrium (at a given temperature and pressure), the molar free energy is

More in vapour phase

More in liquid phase

Same in both the phases

Replaced by chemical potential which is more in vapour phase

4

Molecular size

Temperature

Volume

Pressure

4

Path

Point

State

None of these