4

# If two gases have same reduced temperature and reduced pressure, then they will have the same

Volume

Mass

Critical temperature

None of these

D. None of these

4

# Pick out the correct statement.

Compression ratio of an Otto engine is comparatively higher than a diesel engine

Efficiency of an Otto engine is higher than that of a diesel engine for the same compression ratio

Otto engine efficiency decreases with the rise in compression ratio, due to decrease in work produced per quantity of heat

Diesel engine normally operates at lower compression ratio than an Otto engine for an equal output of work

4

# Boyle's law for gases states that

P ∝ 1/V, when temperature is constant

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

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

P/V = constant, for any gas

4

# Which of the following processes cannot be made reversible even under ideal condition of operation?

Free expansion of a gas

Compression of air in a compressor

Expansion of steam in a turbine

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

4

# Rotary lime kiln is an example of a/an __________ system.

Closed

Open

Isolated

Non-thermodynamic

4

# At triple point (for one component system), vapour pressure of solid as compared to that of liquid will be

More

Less

Same

More or less; depending on the system

4

V1/V2

V2/V1

V1 - V2

V1.V2

4

Negative

Zero

Infinity

None of these

4

# Chemical potential of ith component of a system is given by

μi = (∂F/∂ni)T, P, ni

μi = (∂A/∂ni)T, P, ni

μi = (∂F/∂ni)T, P

μi = (∂A/∂ni)T, P

4

# Entropy of an ideal gas depends upon its

Pressure

Temperature

Both (A) & (B)

Neither (A) nor (B)

4

# Pick out the correct statement.

Entropy and enthalpy are path functions

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

All the natural processes are reversible in nature

Work is a state function

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

# Cp of a gas at its critical temperature and pressure

Becomes zero

Becomes infinity

Equals 1 kcal/kmol °K

Equals 0.24 kcal/kmol °K

4

# Pick out the wrong statement

Phase rule variables are intensive properties

Heat and work are both state function

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

CP and CV are state function

4

Pressure

Volume

Mass

None of these

4

# Pick out the wrong statement.

System (of partially miscible liquid pairs), in which the mutual solubility increases with rise in temperature, are said to possess an upper consolute temperature

Systems, in which the mutual solubility increases with decrease in temperature, are said to possess lower consolute temperature

Nicotine-water system shows both an upper as well as a lower consolute temperature, implying that they are partially miscible between these two limiting temperatures

None of these

4

None of these

4

Critical

Boyle

Inversion

Reduced

4

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

Critical temperature

Melting point

Freezing point

Both (B) and (C)

4

# Gibbs free energy per mole for a pure substance is equal to the

Latent heat of vaporisation

Chemical potential

Molal boiling point

Heat capacity

4

# The intensive properties are

Molar volume, density, viscosity and boiling point

Refractive index and surface tension

Both (A) and (B)

None of these

4

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

Entropy

Internal energy

Enthalpy

Gibbs free energy

4

# In an irreversible process

Tds = dE - dW = 0

dE - dW - Tds = 0

Tds - dE + dW < 0

Tds - dT + dW < 0

4

Positive

Negative

Zero

Infinity

4

# The internal energy of an incompressible fluid depends upon its

Pressure

Temperature

Both (A) & (B)

Neither (A) nor (B)

4

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

A homogeneous solution (say of phenol water) is formed

Mutual solubility of the two liquids shows a decreasing trend

Two liquids are completely separated into two layers

None of these

4

# High __________ is an undesirable property for a good refrigerant.

Specific heat

Latent heat of vaporisation

Viscosity

Specific vapor volume

4

# The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be

More

Less

Same

Data insufficient to predict

4

# Which of the following is a widely used refrigerant in vapour compression refrigeration system (using large centrifugal compressor)?

Freon

Liquid sulphur dioxide

Methyl chloride

Ammonia

4

# Activity co-efficient is a measure of the

Departure from ideal solution behaviour

Departure of gas phase from ideal gas law

Vapour pressure of liquid

None of these