4

# In any spontaneous process,

Only F decreases

Only A decreases

Both F and A decreases

Both F and A increase

C. Both F and A decreases

4

# When a gas is expanded from high pressure region to low pressure region; temperature change occurs. This phenomenon is related to the

Gibbs-Duhem equation

Gibbs-Helmholtz equation

Third law of thermodynamics

Joule-Thomson effect

4

Minimum

Zero

Maximum

None of these

4

P + F - C = 2

C = P - F + 2

F = C - P - 2

P = F - C - 2

4

# The total change in the enthalpy of a system is independent of the

Number of intermediate chemical reactions involved

Pressure and temperature

State of combination and aggregation in the beginning and at the end of the reaction

None of these

4

# (∂E/∂T)V is the mathematical expression for

CV

Enthalpy change

Free energy change

None of these

4

+ve

0

-ve

4

# In an irreversible process

Tds = dE - dW = 0

dE - dW - Tds = 0

Tds - dE + dW < 0

Tds - dT + dW < 0

4

Specific volume

Temperature

Mass

Pressure

4

# Fugacity and pressure are numerically equal, when the gas is

In standard state

At high pressure

At low temperature

In ideal state

4

# The expression, nCv(T2 - T1), is for the __________ of an ideal gas.

Co-efficient of thermal expansion

Compressibility

None of these

4

Enthalpy

Entropy

Pressure

None of these

4

# Pick out the wrong statement.

An ideal liquid or solid solution is defined as one in which each component obeys Raoult's law

If Raoult's law is applied to one component of a binary mixture; Henry's law or Raoult's law is applied to the other component also

Henry's law is rigorously correct in the limit of infinite dilution

None of these

4

# If the vapour pressure at two temperatures of a solid phase in equilibrium with its liquid phase are known, then the latent heat of fusion can be calculated by the

Maxwell's equation

Clausius-Clapeyron Equation

Van Laar equation

Nernst Heat Theorem

4

# Chemical engineering thermodynamics is concerned with the __________ in/of chemical processes.

Reaction mechanism

Calculation of rates

Energy transformation from one form to another

None of these

4

# The expression for entropy change, ΔS = n Cp . ln (T2/T1), is valid for the __________ of a substance.

Simultaneous pressure & temperature change

Heating

Cooling

Both (B) and (C)

4

Equilibrium

4

# Pick out the correct statement.

Like internal energy and enthalpy, the absolute value of standard entropy for elementary substances is zero

Melting of ice involves increase in enthalpy and a decrease in randomness

The internal energy of an ideal gas depends only on its pressure

Maximum work is done under reversible conditions

4

# If the heat of solution of an ideal gas in a liquid is negative, then its solubility at a given partial pressure varies with the temperature as

Solubility increases as temperature increases

Solubility increases as temperature decreases

Solubility is independent of temperature

Solubility increases or decreases with temperature depending on the Gibbs free energy change of solution

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

Zero

One

Two

Three

4

# Which of the following identities can be most easily used to verify steam table data for superheated steam?

(∂T/∂V)S = (∂p/∂S)V

(∂T/∂P)S = (∂V/∂S)P

(∂P/∂T)V = (∂S/∂V)T

(∂V/∂T)P = -(∂S/∂P)T

4

# The chemical potential of any constituent of an ideal solution depends on the __________ of the solution.

Temperature

Pressure

Composition

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

4

# A closed system is cooled reversibly from 100°C to 50°C. If no work is done on the system

its internal energy (U) decreases and its entropy (S) increases

U and S both decreases

U decreases but S is constant

U is constant but S decreases

4

# The melting point of paraffin wax (which contracts on solidification) __________ with pressure rise.

Increases

Decreases

Remains unchanged

Decreases linearly

4

Entropy

Temperature

Internal energy

Enthalpy

4

0.5

3.5

4.5

8.5

4

V/T = Constant

V ∝ 1/T

V ∝ 1/P

PV/T = Constant

4

Only ΔE = 0

Only ΔH =0

ΔE = ΔH = 0

dQ = dE

4

# Specific/molar Gibbs free energy for a pure substance does not change during

Sublimation

Vaporisation

Melting

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