Chemical Engineering Mcqs

The overall heat transfer co-efficient for a shell and tube heat exchanger for clean surfaces is U0 = 400 W/m2.K. The fouling factor after one year of operation is found to be hd0 = 2000 W/m2.K. The overall heat transfer co-efficient at this time is _____________________?

• (A)  1200 W/m2.K
• (B)  894 W/m2.K
• (C)  333 W/m2.K
• (D)  287 W/m2.K

Answer

Submitted By :Ali Uppal

Cpμ/K is termed as the ______________ number?

• (A)  Grashoff
• (B)  Nusselt
• (C)  Prandtl
• (D)  Stanton

Answer

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A black body does not ____________ radiation?

• (A)  Absorb or emit
• (B)  Refract
• (C)  Reflect
• (D)  Both

Answer

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An equipment which converts the latent or sensible heat of one fluid into the latent heat of vaporisation of another, is called a_________________?

• (A)  Boiler
• (B)  Heat exchanger
• (C)  Recuperator
• (D)  Regenerator

Answer

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Fresh orange juice contains 12% (by weight) solids and the rest water 90% of the fresh juice is sent to an evaporator to remove water and subsequently mixed with the remaining 10% of fresh juice. The resultant product contains 40% solids. The kg of water removed from 1 kg fresh juice is__________________?

• (A)  0.4
• (B)  0.5
• (C)  0.6
• (D)  0.7

Answer

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Sensible heat absorbed by 1 lb of water when it is heated from 32 to 212°F may be around ______________ BTU?

• (A)  180
• (B)  970
• (C)  3.97
• (D)  Data insufficient, can’t be predicted

Answer

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Stefan’s block body radiation law can also be derived from ______________ law?

• (A)  Kirchoff’s
• (B)  Planck’s
• (C)  Fourier’s
• (D)  None of these

Answer

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What is the geometric mean of two heat transfer areas A1 and A2 ?

• (A)  √(A1 . A2)
• (B)  √(A1 + A2)
• (C)  ½ √(A1 . A2)
• (D)  2 √(A1 . A2)

Answer

Submitted By :Ali Uppal

The ratio of velocity head to tube side return loss in case of a multipass shell and tube heat exchanger is ________________?

• (A)  2
• (B)  1/2
• (C)  4
• (D)  1/4

Answer

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Which has the lowest Prandtl number ?

• (A)  Liquid metal
• (B)  Aqueous solution
• (C)  Water
• (D)  Lube oil

Answer

Submitted By :Ali Uppal