Chemical Engineering Thermodynamics

Question: A cyclic engine exchanges heat with two reservoirs maintained at 100 and 300°C respectively. The maximum work (in J) that can be obtained from 1000 J of heat extracted from the hot reservoir is
[A].

349

[B].

651

[C].

667

[D].

1000

Answer: Option A

Explanation:

No answer description available for this question.

Question: As pressure approaches zero, the ratio of fugacity to pressure (f/P) for a gas approaches
[A].

zero

[B].

unity

[C].

infinity

[D].

an indeterminate value

Answer: Option B

Explanation:

No answer description available for this question.

Question: At 60° C, vapour pressure of methanol and water are 84.562 kPa and 19.953 kPa respectively. An aqueous solution of methanol at 60° C exerts a pressure of 39.223 kPa; the liquid phase and vapour phase mole fractions of methanol are 0.1686 and 0.5714 respectively. Activity co-efficient of methanol is
[A].

1.572

[B].

1.9398

[C].

3.389

[D].

4.238

Answer: Option A

Explanation:

No answer description available for this question.

Question: A solid metallic block weighing 5 kg has an initial temperature of 500°C. 40 kg of water initially at 25°C is contained in a perfectly insulated tank. The metallic block is brought into contact with water. Both of them come to equilibrium. Specific heat of block material is 0.4 kJ.kg-1. K-1. Ignoring the effect of expansion and contraction and also the heat capacity to tank, the total entropy change in kJ.kg-1 , K-1 is
[A].

-1.87

[B].

0

[C].

1.26

[D].

3.91

Answer: Option B

Explanation:

No answer description available for this question.

Question: For water at 300°C, it has a vapour pressure 8592.7 kPa and fugacity 6738.9 kPa Under these conditions, one mole of water in liquid phase has a volume of 25.28 cm3 and that in vapour phase in 391.1 cm3.Fugacity of water (in kPa) at 9000 kPa will be
[A].

6738.9

[B].

6753.5

[C].

7058.3

[D].

9000

Answer: Option B

Explanation:

No answer description available for this question.

Question: One mole of nitrogen at 8 bar and 600 K is contained in a piston-cylinder arrangement. It is brought to 1 bar isothermally against a resisting pressure of 1 bar. The work done (in Joules) by the gas is
[A].

30554

[B].

10373

[C].

4988.4

[D].

4364.9

Answer: Option B

Explanation:

No answer description available for this question.

Question: For organic compounds, group contribution method can be used for the estimation of
[A].

critical properties.

[B].

specific gravity.

[C].

specific volume.

[D].

thermal conductivity.

Answer: Option A

Explanation:

No answer description available for this question.

Question: Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = Cp/Cv = 7/5) and the process to be reversible, is
[A].

300(32/7)

[B].

300(33/5)

[C].

300(333/7)

[D].

300(35/7)

Answer: Option A

Explanation:

No answer description available for this question.

Question: A reasonably general expression for vapour-liquid phase equilibrium at low to moderate pressure is Φi yi P = Yi xi fi° where, Φ is a vapor fugacity component, Yi is the liquid activity co-efficient and fi° is the fugacity of the pure component i. the Ki value (Yi = Ki xi) is therefore, in general a function of
[A].

temperature only.

[B].

temperature and pressure only.

[C].

temperature, pressure and liquid composition xi only.

[D].

temperature, pressure, liquid composition xi and vapour composition yi.

Answer: Option C

Explanation:

No answer description available for this question.

Question: On a P-V diagram of an ideal gas, suppose a reversible adiabatic line intersects a reversible isothermal line at point A. Then at a point A, the slope of the reversible adiabatic line (∂P/∂V)s and the slope of the reversible isothermal line (∂P/∂V)T are related as (where, y = Cp/Cv)
[A].

(∂P/∂V)S = (∂P/∂V)T

[B].

(∂P/∂V)S = [(∂P/∂V)T]Y

[C].

(∂P/∂V)S = y(∂P/∂V)T

[D].

(∂P/∂V)S = 1/y(∂P/∂V)T

Answer: Option C

Explanation:

No answer description available for this question.