Month: February 2019

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 ?

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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

Raoult’s law does not apply, when the___________________?

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Raoult’s law does not apply, when the___________________?

A. Size of component molecules are not equal
B. Attractive forces between like and unlike molecules in the solution are approximately equal
C. Component molecules are non-polar
D. Chemical combination or molecular association between unlike molecules takes place in the
formation of solution

In most of the mechanically agitated liquid-liquid extractors, baffles or horizontal compartmental plates are provided, which helps in_________________?

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In most of the mechanically agitated liquid-liquid extractors, baffles or horizontal compartmental plates are provided, which helps in_________________?

A. Reducing the axial mixing
B. Increasing the rate of extraction
C. Maintaining the concentration difference between the two phases
D. All A , B & C.

Blowdown in a cooling tower__________________?

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Blowdown in a cooling tower__________________?

A. Means discarding a small fraction of circulating water to prevent and limit the concentration
of salt and impurities
B. Increases the scale forming tendencies of water
C. Is undesirable
D. All A., B. & C.

pertaining to the analogy between equations of heat and mass transfer operations ?

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pertaining to the analogy between equations of heat and mass transfer operations ?

Pick out the wrong statement
A. Sherwood number in mass transfer is analogous to Nusselt number in heat transfer
B. Prandtl number in heat transfer is analogous to Schmidt number in mass transfer
C. Reynolds number in mass transfer is analogous to Grashoff number in heat transfer
D. Reynolds number remains the same in both heat and mass transfer