Practice Pakistan's most useful MCQs for competitive exams

The slope of 9-line is determined by the__________________?

• (A)  Reflux ratio
• (B)  Plate efficiency to be achieved
• (C)  Thermal condition of the feed
• (D)  Relative volatility

Answer

Submitted By :Ali Uppal

For a binary mixture with low relative volatility___________________?

• (A)  Use steam distillation
• (B)  Use molecular distillation
• (C)  Use high pressure distillation
• (D)  An azeotrope may be formed during distillation

Answer

Submitted By :Ali Uppal

The interfacial area per unit volume of dispersion, in a gas-liquid contactor, for fractional hold up of gas = 0.1 and gas bubble diameter = 0.5 mm is given by (in m2/m3)_________________?

• (A)  500
• (B)  1200
• (C)  900
• (D)  800

Answer

Submitted By :Ali Uppal

Plate efficiency in a distillation column is reduced due to the ______________ of liquid?

• (A)  Entrainment
• (B)  Foaming
• (C)  Weeping & dumping
• (D)  All

Answer

Submitted By :Ali Uppal

In extraction, as the temperature increases, the area of heterogeneity (area covered by binodal curve)____________________?

• (A)  Decreases
• (B)  Increases
• (C)  Remains unchanged
• (D)  None of these

Answer

Submitted By :Ali Uppal

The wet and ‘dry bulb temperature for a vapour-gas mixture are 25°C and 30°C respectively. If the mixture is heated to 45°C at constant pressure, the wet bulb temperature will be ______________ °C ?

• (A)  25
• (B)  > 25
• (C)  < 25
• (D)  – 25

Answer

Submitted By :Ali Uppal

Humidity chart is useful for the solution of problems concerning condensation, vaporisation and air conditioning. At a given dry bulb temperature, value of humidity obtained from the humidity chart directly, is in terms of _______________ humidity?

• (A)  Molal
• (B)  Relative
• (C)  Percentage
• (D)  None of these

Answer

Submitted By :Ali Uppal

Powdery materials can be guarded against caking tendency on storage by___________________?

• (A)  Providing irregular grain size
• (B)  Providing minimum percentage of voids
• (C)  Having maximum possible points of contact
• (D)  None of these

Answer

Submitted By :Ali Uppal

Leaching of uranium ore and gold ore is done in_____________________?

• (A)  Centrifugal extractor
• (B)  Pachuca tanks
• (C)  Bollman extractor
• (D)  None of these

Answer

Submitted By :Ali Uppal

For a ternary mixture, in which equilateral triangular co-ordinate is used in leaching and extraction, a ____________ of the equilateral triangular co-ordinates?

• (A)  Binary mixture is represented by the apex
• (B)  Binary mixture is represented by any point inside
• (C)  Ternary mixture is represented by the sides
• (D)  Pure component is represented by the apex

Answer

Submitted By :Ali Uppal