4

# For an ideal gas, the activity co-efficient is

Directly proportional to pressure

Inversely proportional to pressure

Unity at all pressures

None of these

C. Unity at all pressures

4

Logarithmic

Arithmetic

Geometric

Harmonic

4

# What happens in a reversible adiabatic compression?

Heating occurs

Cooling occurs

Pressure is constant

Temperature is constant

4

# Fugacity is a measure of the

Escaping tendencies of the same substance in different phases of a system

Relative volatility of a mixture of two miscible liquids

Behaviour of ideal gases

None of these

4

# Pick out the wrong statement.

At constant pressure, solubility of a gas in a liquid diminishes with rise in temperature

Normally, the gases which are easily liquefied are more soluble in common solvents

The gases which are capable of forming ions in aqueous solution are much more soluble in water than in other solvents

At constant pressure, solubility of a gas in a liquid increases with rise in temperature

4

Minimum

Zero

Maximum

None of these

4

Free energy

Entropy

Refractive index

None of these

4

# Heat of formation of an element in its standard state is

0

< 0

> 0

A function of pressure

4

# The expression for entropy change given by, ΔS = - nR ln (P2/P1), holds good for

Expansion of a real gas

Reversible isothermal volume change

Heating of an ideal gas

Cooling of a real gas

4

Isochoric

Isobaric

Isothermal

4

0

273

25

None of these

4

# The equation, PV = nRT, is best obeyed by gases at

Low pressure & high temperature

High pressure & low temperature

Low pressure & low temperature

None of these

4

30554

10373

4988.4

4364.9

4

1

2

3

4

4

# Mollier diagram is a plot of

Temperature vs. enthalpy

Temperature vs. enthalpy

Entropy vs. enthalpy

Temperature vs. internal energy

4

Molecular size

Temperature

Volume

Pressure

4

0

1

2

3

4

# An isentropic process is carried out at constant

Volume

Pressure

Temperature

All (A), (B) and (C)

4

-1.87

0

1.26

3.91

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

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

Critical temperature

Melting point

Freezing point

Both (B) and (C)

4

# Which of the following is not an intensive property?

Molar heat capacity

Internal energy

Viscosity

None of these

4

# When liquid and vapour phase of multi-component system are in equilibrium (at a given temperature and pressure), then chemical potential of each component is

Same in both the phases

Zero in both the phases

More in vapour phase

More in liquid phase

4

0

Maximum

Minimum

4

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

Turbine

Heat engine

Reversed heat engine

None of these

4

# A gas shows deviation from ideal behaviour at

Low pressure and high temperature

Low pressure and low temperature

Low temperature and high pressure

High temperature and high pressure

4

Gibbs-Duhem

Maxwell's

Clapeyron

None of these

4

# The freezing point of a liquid decreases when the pressure is increased, if the liquid __________ while freezing.

Contracts

Expands

Does not change in volume

Either (A), (B) or (C)

4

Mass

Momentum

Energy

None of these

4

Heat pump

Heat engine

Carnot engine

None of these