BE/B Eng Bachelor of Engineering Bachelor of Chemical Engineering 5

Question 1

In a binary liquid-vapor system, what is an azeotrope?

Accepted Answer

A mixture whose vapor composition equals its liquid composition at a given T and P

Answer

A mixture where both components are completely immiscible

Answer

The composition at maximum boiling point for any binary system

Answer

A mixture that cannot be distilled under any conditions

Question 2

Which dimensionless number represents the ratio of momentum diffusivity to thermal diffusivity in a fluid?

Accepted Answer

Prandtl number

Answer

Nusselt number

Answer

Schmidt number

Answer

Biot number

Question 3

In process design, a 'pinch point' in a heat exchanger network represents:

Accepted Answer

The point where the hot and cold composite curves approach most closely (minimum ΔT)

Answer

The location of maximum pressure drop

Answer

The operating pressure limit of the heat exchanger

Answer

The optimal reflux ratio in a distillation system

Question 4

What is the purpose of a 'recycle stream' in a chemical process?

Accepted Answer

To return unreacted feed material to the reactor to improve overall conversion

Answer

To cool the reactor by removing heat continuously

Answer

To purge inert gases that accumulate in the system

Answer

To separate byproducts from the main product stream

Question 5

In electrochemical engineering, Faraday's law states that the mass of material deposited or dissolved is proportional to:

Accepted Answer

The total charge passed through the electrolyte

Answer

The voltage applied across the electrodes

Answer

The concentration of ions in solution

Answer

The surface area of the electrode

Question 6

Which type of flow regime in a fluidized bed is characterized by solid particles behaving like a boiling liquid with large bubbles rising through the bed?

Accepted Answer

Bubbling fluidization

Answer

Fixed bed regime

Answer

Pneumatic transport (dilute phase)

Answer

Slugging flow at low velocities

Question 7

What is the primary advantage of using a packed column over a plate column in distillation?

Accepted Answer

Packed columns have lower pressure drop, making them suitable for vacuum distillation

Answer

Packed columns handle higher liquid flow rates without flooding

Answer

Packed columns are cheaper to fabricate for large diameters

Answer

Packed columns allow easier side-draw product removal