Mass Transfer The mass transfer co-efficient for a solid sphere of radius 'a' dissolving in a large volume of quiescent liquid, in which D is the diffusivity of solute, is Proportional to √D D/a Dependent on the Reynolds number D/2a Proportional to √D D/a Dependent on the Reynolds number D/2a ANSWER DOWNLOAD EXAMIANS APP
Mass Transfer In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions:(i) Reflux stream is completely liquid and is at its bubble point.(ii) Reflux stream is below its bubble point. Condenser load is the same in both the cases but reboiler load is higher in case (ii) Both condensor and reboiler loads are higher in case (ii) as compared to case (i) Condenser and reboiler loads are the same in both the cases Reboiler load is the same in both the cases but condenser load is higher in case (ii) Condenser load is the same in both the cases but reboiler load is higher in case (ii) Both condensor and reboiler loads are higher in case (ii) as compared to case (i) Condenser and reboiler loads are the same in both the cases Reboiler load is the same in both the cases but condenser load is higher in case (ii) ANSWER DOWNLOAD EXAMIANS APP
Mass Transfer An aqueous solution of methanol is to be distilled in a tray column. High pressure steam is available as a source of heat. For a given reflux ratio and overhead composition, two options are being explored; (i) a reboiler is used and (ii) no reboiler is used but steam is fed directly to the bottom of the column. As compared to option (i), in option (ii) Composition of the residue remains unchanged More number of trays are required and the residue composition is more dilute in methanol More number of trays are required but the residue composition remains unchanged Less number of trays are required Composition of the residue remains unchanged More number of trays are required and the residue composition is more dilute in methanol More number of trays are required but the residue composition remains unchanged Less number of trays are required ANSWER DOWNLOAD EXAMIANS APP
Mass Transfer Which of the following employs an accessory known as 'drift eliminator' ? Rotary dryer Mechanical draft cooling tower Rotating disc contactor Multiple effect evaporator Rotary dryer Mechanical draft cooling tower Rotating disc contactor Multiple effect evaporator ANSWER DOWNLOAD EXAMIANS APP
Mass Transfer The mass diffusivity, the thermal diffusivity and the eddy momentum diffusivity are same for, NPr = NSc = __________ 3 2 1 4 3 2 1 4 ANSWER DOWNLOAD EXAMIANS APP
Mass Transfer For a binary mixture distillation process, the degree of freedom is 2. However, if the pressure is fixed in this process, the number of independent variables in this process will be 1 2 3 1 2 3 ANSWER DOWNLOAD EXAMIANS APP