5. In condensers used in thermal power plants, steam is normally used in shell side and cooling water on the tube side, because of the reason that
Options
A. compared to the mass flow rate of cooling water, the rate of condensation of steam is invariably smaller.
B. maintaining vacuum on tube side is more difficult than that on the shell side.
C. water velocity can be increased conveniently to increase the overall heat transfer co-efficient because of its lower specific volume compared to steam.
D. condenser can act as a storage unit for condensed steam.
Correct Answer: water velocity can be increased conveniently to increase the overall heat transfer co-efficient because of its lower specific volume compared to steam.
6. The order of preference for feedstock to a catalytic reformer is
Options
A. catalytic naphtha - coking naphtha - virgin naphtha.
B. coking naphtha - virgin naphtha - catalytic naphtha.
C. virgin naphtha - catalytic naphtha - coking naphtha.
D. virgin naphtha - coking naphtha - catalytic naphtha.
7. Assuming applicability of ideal gas law, the pure component volume of the vapor in a saturated gas can be calculated from theoretical relationship. The volumetric composition of a vapor saturated gas is independent of the
A. To make 100 kg of a solution containing 40% salt by mixing solution A (containing 25% salt) and solution B (containing 50% salt), the amount of solution A required is 40 kg.
B. 1.2 gm atoms of carbon and 1.5 gm moles of oxygen are reacted to give 1 gm mole of carbon dioxide. The limiting reactant is carbon. The percent excess reactant supplied is 25.
C. A gas bubble at a pressure of Pg is passed through a solvent with a saturation vapour pressure of Ps. If the time of passage of the bubble is long and air is insoluble in the solvent, the mole fraction of solvent in the bubble will be equal to Ps/Pg.
D. A supersaturated solution of a sparingly soluble solute, at a concentration of C, is being fed to a crystalliser at a volumetric flow rate of V. The solubility .of the solute is C1. The output rate of solids from an efficient crystalliser is (C + C1) V.
Correct Answer: A supersaturated solution of a sparingly soluble solute, at a concentration of C, is being fed to a crystalliser at a volumetric flow rate of V. The solubility .of the solute is C1. The output rate of solids from an efficient crystalliser is (C + C1) V.