A reasonably general expression for vapourliquid phase equilibrium at low to moderate pressure is φ_i y_i P = Y_i x_if_i° where, Φ is a vapor fugacity component, Y_i is the liquid activity co-efficient and f_i° is the fugacity of the pure component i. the K_i value (Y_i = K_i x_i) is therefore, in general a function of

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A reasonably general expression for vapourliquid phase equilibrium at low to moderate pressure is φ_i y_i P = Y_i x_if_i° where, Φ is a vapor fugacity component, Y_i is the liquid activity co-efficient and f_i° is the fugacity of the pure component i. the K_i value (Y_i = K_i x_i) is therefore, in general a function of

A. Temperature only

B. Temperature and pressure only

C. Temperature, pressure and liquid composition x_i only

D. Temperature, pressure, liquid composition x_i and vapour composition yi

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1st law of thermodynamics is nothing but the law of conservation of

A. Momentum

B. Mass

C. Energy

D. None of these

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

A. Expansion of a real gas

B. Reversible isothermal volume change

C. Heating of an ideal gas

D. Cooling of a real gas

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The equation, (d log_e PA/d log_e xA) = (d log_e PA/d log_e xB) applicable to a binary solution of components. A and B in equilibrium with their vapors at constant temperature and pressure is called the __________ equation.

A. Van Laar

B. Margules

C. Gibbs-Duhem

D. Gibbs-Duhem-Margules

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Pick out the wrong statement.

A. The conversion for a gas phase reaction increases with decrease in pressure, if there is an increase in volume accompanying the reaction

B. With increase in temperature, the equilibrium constant increases for an exothermic reaction

C. The equilibrium constant of a reaction depends upon temperature only

D. The conversion for a gas phase reaction increases with increase in pressure, if there is a decrease in volume accompanying the reaction

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Number of phases in a colloidal system is:

A. 1

B. 2

C. 3

D. 4

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For an ideal liquid solution, which of the following is unity?

A. Activity

B. Fugacity

C. Activity co-efficient

D. Fugacity co-efficient

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Heating of water under atmospheric pressure is an __________ process.

A. Isochoric

B. Isobaric

C. Adiabatic

D. Isothermal

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In case of vapour compression refrigeration system, elevating the evaporator temperature (keeping the condenser temperature constant) results in

A. Enhanced COP

B. Decreased COP

C. No change in the value of COP

D. Increased or decreased COP; depending upon the type of refrigerant

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The reaction A (l) → R(g) is allowed to reach equilibrium conditions in an autoclave. At equilibrium, there are two phases, one a pure liquid phase of A and the other a vapor phase of A, R and S. Initially A alone is present. The numbers of degrees of freedom are:

A. 1

B. 2

C. 3

D. 0

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For a constant volume process __________ by the system is used only to increase the internal energy.

A. Heat absorbed

B. Work done

C. Both (A) & (B)

D. Neither (A) nor (B)

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When a gas in a vessel expands, its internal energy decreases. The process involved is

A. Reversible

B. Irreversible

C. Isothermal

D. Adiabatic

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Fugacity is most helpful in

A. Representing actual behaviour of real gases

B. Representing actual behaviour of ideal gases

C. The study of chemical equilibria involving gases at atmospheric pressure

D. None of these

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What happens in a reversible adiabatic compression?

A. Heating occurs

B. Cooling occurs

C. Pressure is constant

D. Temperature is constant

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

A. Low pressure & high temperature

B. High pressure & low temperature

C. Low pressure & low temperature

D. None of these

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For an isothermal process, the internal energy of a gas

A. Increases

B. Decreases

C. Remains unchanged

D. Data insufficient, can't be predicted

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The amount of heat required to decompose a compound into its elements is __________ the heat of formation of that compound from its elements.

A. Less than

B. More than

C. Same as

D. Not related to

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Boiling of liquid is accompanied with increase in the

A. Vapor pressure

B. Specific Gibbs free energy

C. Specific entropy

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

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The value of gas constant 'R' is

A. 1.987 cal/gm mole °K

B. 1.987 BTU/lb. mole °R

C. Both (A) and (B)

D. Neither (A) nor (B)

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If we increase the pressure on a substance (which is at its triple point), then the triple point

A. Increases

B. Decreases

C. Remains unchanged

D. May increase or decrease; depends on the substance

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

A. Entropy

B. Internal energy

C. Enthalpy

D. Gibbs free energy

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A/an __________ system is exemplified by a vessel containing a volatile liquid in contact with its vapor.

A. Isolated

B. Closed

C. Open

D. None of these

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Isotherm on an enthalpy-concentration diagram, for an ideal solution will be a

A. Straight line

B. Sine curve

C. Parabola

D. Hyperbola

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Which is not constant for an ideal gas?

A. (∂P/∂V)_T

B. (∂V/∂T)_P

C. (∂P/∂V)_V

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

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Chemical potential of ith component of a system is given by

A. μ_i = (∂F/∂n_i)_{T, P, ni}

B. μ_i = (∂A/∂n_i)_{T, P, ni}

C. μ_i = (∂F/∂n_i)_{T, P}

D. μ_i = (∂A/∂n_i)_{T, P}

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Air-refrigeration cycle

A. Is the most efficient of all refrigeration cycles

B. Has very low efficiency

C. Requires relatively large quantities of air to achieve a significant amount of refrigeration

D. Both (B) and (C)

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Which of the following non-flow reversible compression processes require maximum work?

A. Adiabatic process

B. Isothermal process

C. Isobaric process

D. All require same work

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Equilibrium constant decreases as the temperature

A. Increases, for an exothermic reaction

B. Decreases, for an exothermic reaction

C. Increases, for an endothermic reaction

D. None of these

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The standard state of a gas (at a given temperature) is the state in which fugacity is equal to

A. Unity

B. Activity

C. Both (A) & (B)

D. Neither (A) nor (B)

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Specific __________ does not change during phase change at constant temperature and pressure.

A. Entropy

B. Gibbs energy

C. Internal energy

D. Enthalpy

Discuss this answer

In a reversible process

A. Tds = dE + dW

B. dE - dW = Tds

C. dW - dE = Tds

D. Tds - dW + dE >0

Discuss this answer

Accepted Answer

C. Temperature, pressure and liquid composition x_i only

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Related Questions

1st law of thermodynamics is nothing but the law of conservation of

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

The equation, (d log_e PA/d log_e xA) = (d log_e PA/d log_e xB) applicable to a binary solution of components. A and B in equilibrium with their vapors at constant temperature and pressure is called the __________ equation.

Pick out the wrong statement.

Number of phases in a colloidal system is:

For an ideal liquid solution, which of the following is unity?

Heating of water under atmospheric pressure is an __________ process.

In case of vapour compression refrigeration system, elevating the evaporator temperature (keeping the condenser temperature constant) results in

The reaction A (l) → R(g) is allowed to reach equilibrium conditions in an autoclave. At equilibrium, there are two phases, one a pure liquid phase of A and the other a vapor phase of A, R and S. Initially A alone is present. The numbers of degrees of freedom are:

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When a gas in a vessel expands, its internal energy decreases. The process involved is

Fugacity is most helpful in

What happens in a reversible adiabatic compression?

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

For an isothermal process, the internal energy of a gas

The amount of heat required to decompose a compound into its elements is __________ the heat of formation of that compound from its elements.

Boiling of liquid is accompanied with increase in the

The value of gas constant 'R' is

If we increase the pressure on a substance (which is at its triple point), then the triple point

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

A/an __________ system is exemplified by a vessel containing a volatile liquid in contact with its vapor.

Isotherm on an enthalpy-concentration diagram, for an ideal solution will be a

Which is not constant for an ideal gas?

Chemical potential of ith component of a system is given by

Air-refrigeration cycle

Which of the following non-flow reversible compression processes require maximum work?

Equilibrium constant decreases as the temperature

The standard state of a gas (at a given temperature) is the state in which fugacity is equal to

Specific __________ does not change during phase change at constant temperature and pressure.

In a reversible process

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Correct Answer :

Show all Chemical Engineering Thermodynamics MCQ

Related Questions

1st law of thermodynamics is nothing but the law of conservation of

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

The equation, (d loge PA/d loge xA) = (d loge PA/d loge xB) applicable to a binary solution of components. A and B in equilibrium with their vapors at constant temperature and pressure is called the __________ equation.

Pick out the wrong statement.

Number of phases in a colloidal system is:

For an ideal liquid solution, which of the following is unity?

Heating of water under atmospheric pressure is an __________ process.

In case of vapour compression refrigeration system, elevating the evaporator temperature (keeping the condenser temperature constant) results in

The reaction A (l) → R(g) is allowed to reach equilibrium conditions in an autoclave. At equilibrium, there are two phases, one a pure liquid phase of A and the other a vapor phase of A, R and S. Initially A alone is present. The numbers of degrees of freedom are:

For a constant volume process __________ by the system is used only to increase the internal energy.

When a gas in a vessel expands, its internal energy decreases. The process involved is

Fugacity is most helpful in

What happens in a reversible adiabatic compression?

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

For an isothermal process, the internal energy of a gas

The amount of heat required to decompose a compound into its elements is __________ the heat of formation of that compound from its elements.

Boiling of liquid is accompanied with increase in the

The value of gas constant 'R' is

If we increase the pressure on a substance (which is at its triple point), then the triple point

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

A/an __________ system is exemplified by a vessel containing a volatile liquid in contact with its vapor.

Isotherm on an enthalpy-concentration diagram, for an ideal solution will be a

Which is not constant for an ideal gas?

Chemical potential of ith component of a system is given by

Air-refrigeration cycle

Which of the following non-flow reversible compression processes require maximum work?

Equilibrium constant decreases as the temperature

The standard state of a gas (at a given temperature) is the state in which fugacity is equal to

Specific __________ does not change during phase change at constant temperature and pressure.

In a reversible process

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

The equation, (d log_e PA/d log_e xA) = (d log_e PA/d log_e xB) applicable to a binary solution of components. A and B in equilibrium with their vapors at constant temperature and pressure is called the __________ equation.