Chemical Engineering Mcqs

Conduction occurs in the buffer zone for a fluid flowing through a heated pipe, only when Prandtl number is________________?

• (A)  0.1
• (B)  > 1
• (C)  < 1
• (D)  1

Answer

Submitted By :Ali Uppal

The type of liquor circulation system to be ‘ employed in evaporators (viz. natural or forced circulation) is determined mainly by the ______________ of the liquid?

• (A)  Viscosity
• (B)  Density
• (C)  Thermal conductivity
• (D)  Corrosive nature

Answer

Submitted By :Ali Uppal

For a given ambient air temperature with increase in the thickness of insulation of a hot cylindrical pipe, the rate of heat loss from the surface would ?

• (A)  Decrease
• (B)  Increase
• (C)  First decrease and then increase
• (D)  First increase and then decrease

Answer

Submitted By :Ali Uppal

In a backward feed multiple effect evaporator ___________________ ?

• (A)  Feed is introduced in the first effect
• (B)  Feed flows from low pressure to high pressure
• (C)  No pumps are required between successive effects
• (D)  None of these

Answer

Submitted By :Ali Uppal

Steam is routed through the tube in case of a ______________ evaporator?

• (A)  Basket type
• (B)  Horizontal tube
• (C)  Short tube vertical
• (D)  Long tube vertical

Answer

Submitted By :Ali Uppal

Multiple effect evaporation is generally recommended, when the______________________?

• (A)  Large scale evaporation of liquor is needed
• (B)  Corrosive liquids are to be concentrated
• (C)  Fuel is cheaply available
• (D)  Evaporation on small scale is to be done

Answer

Submitted By :Ali Uppal

1 BTU/hr.ft.°F is equal to _____________ kcal/hr. m.°C?

• (A)  1.49
• (B)  1
• (C)  4.88
• (D)  None of these

Answer

Submitted By :Ali Uppal

A _____________ surface has the maximum thermal emissivity out of the following ?

• (A)  Black & smooth
• (B)  Black & rough
• (C)  White & smooth
• (D)  White & rough

Answer

Submitted By :Ali Uppal

Radiation heat transfer rates does not depend upon the_________________?

• (A)  Type of absorbing surface
• (B)  Distance between the heat source and the object receiving the heat
• (C)  Surface area and temperature of the heat source
• (D)  None of these

Answer

Submitted By :Ali Uppal

If all the conditions and dimensions are same, then the ratio of velocity through the tubes of a double pass heat exchanger to that through the single pass heat exchanger is_________________?

• (A)  1
• (B)  2
• (C)  1/2
• (D)  4

Answer

Submitted By :Ali Uppal