Engineering Questions with Answers - Multiple Choice Questions

# Separation Processes MCQ’s – Graphical Correlations of Thermodynamic Properties

1 - Question

What is a nomograph?
a) A graph containing relationship between two quantities
b) A graph containing relationship between three quantities
c) A graph containing relationship between three or more quantities
d) A graph containing diagrams
Explanation: A nomograph is a a diagram representing the relations between three or more variable quantities by means of a number of scales, so arranged that the value of one variable can be found by a simple geometrical construction, e.g. by drawing a straight line intersecting the other scales at the appropriate values.

2 - Question

The convergence pressure depends on what?
a) Densities of the components
b) Amounts of the components
c) Melting points of the components
d) Boiling points of the components
Explanation: The convergence pressure from the nomograph depends on the boiling points of the components when the K values collapse to 1.0.

3 - Question

What is the convergence pressure for narrow boiling point mixtures?
a) less than 5000psia
b) less than 2500psia
c) less than 1000psia
d) less than 500psia
Explanation: For narrow boiling point range like ethane and propoane the convergence pressure is less than 1000psia.

4 - Question

Why are there no charts available for liquid-liquid distribution?
a) The values are different every time
b) Because of pronounced effect of composition
c) Because the distribution is tough to find
d) There is no convergence pressure
Explanation: No simple charts are available for estimating liquid-liquid distribution because of pronounced effect of composition.

5 - Question

What estimation is available for dilute solutions that are ternary and contain almost immiscible solvents?
a) A tabular distribution of partition coefficients by robins
b) A tabular distribution of partition coefficients by keller
c) A tabular distribution of partition coefficients by Haden
d) A tabular distribution of partition coefficients by Grayson
Explanation: For estimation is available for dilute solutions that are ternary and contain almost immiscible solvents a tabular distribution of partition coefficients by robins is used.

6 - Question

What Is NOT the use of plots of thermodynamic properties?
a) Used to establish correlations.
b) Used to make general observation
c) Used to extrapolate and find unknown quantities
d) Used to know the purity
Explanation: Plots of thermodynamic properties don’t tell us about the purity of components.

7 - Question

Which equation is fitted in the plot of vapor pressure versus temperature?
a) Roult’s law
b) Newton’s law
c) Antoine Equation
d) Gibb’s equation
Explanation: The plots are supposed to fit and follow the Antoine equation.

8 - Question

How are Nomographs used?
a) They give the direct reading
b) By joining the lines and extrapolating
c) By finding out points, joining the lines and extrapolating
d) Nomographs are ancient and thus not used
Explanation: Nomographs are used by finding out points, joining the lines and extrapolating to the desired quantity wanted.

9 - Question

If the partial vapor pressure of the component is 1000pa in the gaseous mixture and the vapor pressure of pure component is 2000pa what is the mole fraction of the solute?
a) 2
b) 1
c) 1.5
d) 0.5
Explanation: Psi/P. Hence xi = 1000/2000=0.5.

10 - Question

What is the K-value if the partial vapor pressure of the component is 360Pa in gaseous mixture and the vapor pressure of pure component is 500Pa.
a) 0.43
b) 0.55
c) 0.72
d) 0.88