Mass Transfer
As the reflux ratio, in a continuous counter-current extraction is increased, the number of stages

Remain unchanged
Decrease
Can either increase or decrease, depends on the system
Increase

ANSWER DOWNLOAD EXAMIANS APP

Mass Transfer
Solvent extraction is the terminology applied to the liquid-liquid extraction, which is preferred for the separation of the components of liquids, when

One of the liquid components has very high affinity towards the solvent
Viscosity of liquid components is very high
Extracting solvent is cheaply & abundantly available
One of the liquid components is heat sensitive

ANSWER DOWNLOAD EXAMIANS APP

Mass Transfer
Pick out the wrong statement pertaining to the rotary dryer.

Rotary dryer is suitable for drying sticky material
Hold up of a rotary drier is defined as the fraction of the dryer volume occupied by the solid at any instant. The best performance for rotary drier is obtained, when the hold up is in the range of 0.
Recommended peripherial speed of a rotary drier is in the range of 10 to 30 metres/minute
Flights (located in the inside shell of rotary dryer) lift the material being dried and shower it down through the current of hot air/gases. It extends from the wall to a distance which is about 8-12%

ANSWER DOWNLOAD EXAMIANS APP