Day 2 (L)

One mole of hydrogen is burned with 20% excess air. If 25% of the hydrogen was burned, the number of moles of nitrogen fed to the furnace is

A binary solution, where A is a low boiler, exhibiting a maximum boiling point, is subjected to flash distillation. If the feed has a concentration in A greater than the azeotropic point, the concentration of the distillate will be

The continuity equation

After 30 min, the constant rate volume collected is ¼ compared to the final total volume of filtrate ending at constant pressure using a plate and frame filter press. If a duplicate pump is installed in parallel with the present pump, determine the new filtration time. Neglect the resistance of the filter medium.

When the liquid flow rate is fixed and the composition of the liquid and gas at the bottom of the absorption tower are fixed, the limiting flow rate to give infinitely tall tower becomes

If the pressure in the upstream side of a membrane is very much higher compared to that in the permeate side, then the concentration of the feed is __________ if the selectivity is 8 and the permeate composition is 0.35 mole fraction.

When the Two-Film Theory is applied to gas absorption, the over-all resistance can be expressed in terms of the individual resistances in the form 1/K_ya = 1/k_ya + m/k_xa.  This is possible because of an important assumption. This assumption is

The primary reason why close steam is used in an open batch steam distillation is to

Pick out the wrong statement: Generally for physical adsorption, a gas of

A layer of pulverized cork 15.2 cm thick is used as a layer of thermal insulation in a flat wall. The temperature of the cold side of the cork is 4.4ºC, and that of the warm side is 82.2ºC. The thermal conductivity of the cork at 0ºC is 0.036 W/m-K and at 93.3ºC is 0.055 W/m-K. The area of the wall is 2.32 m². What is the rate of heat flow through the wall?

Find the filtration rate that can be expected from a basket centrifugal filter using the data below:

Basket height = 12 in.
Inside basket diameter = 26 in.
Rotation Rate = 2000 rpm

Material to be filtered:
gypsum slurry, α =2.52 x 10¹¹ ft/lb
ε = 0.5
Specific gravity of CaSO_{4 •} 2H₂O = 2.65

Assume that the cake is incompressible, filter medium resistance is negligible and the liquid surface corresponds to the filter cake surface and the thickness of the cake is 1 in.

It is a liquid or gas, used to help remove the permeate.

The Pine oil used in froth flotation technique acts as a

Any operation in which one solid is separated from another by floating one of them at or on the surface of a fluid.

A thickener of 500 ft² circular cross-sectional area is available. The tons of solids the thickener can handle per hr day if continuous underflow concentration is 0.6 g/cc is

A flotation modifier used to make a mineral surface amenable to collector coating

Wet solid is to be dried from 40% to 10% in 5 hours under constant drying conditions. The critical moisture content is 20% and the equilibrium moisture content is 7%. All moisture contents are on a dry basis. The time needed to dry from 15% to 5% free moisture content under the same drying conditions is

The unit operation process in which a soluble component is removed from an inert solid by a solvent which preferentially dissolves the soluble matter from the mixture is known as

Operating pressure for solvent extraction operation

In gas absorption, packings are used

The relation connecting the fugacities of various components in a solution with one another and to composition at constant temperature and pressure.

One hundred kg mol/hr of 40 mol of benzene-toluene mixture is fractionated in a plate column at 1 atm. The overhead product must contain 95 mol % benzene and the bottoms must contain 95% by mole of toluene. The feed is saturated liquid. Determine the minimum reflux ratio.

A liquid phase reaction  2A → P with k = 25 cubic feet/ mol-hr is carried out in a PFR. A flow rate of 50 cubic feet per hour containing pure A with initial concentration of A equal to 0.20 lb mol/cubic foot enters the reactor. What reactor volume is required to attain 80% conversion?

In batch open steam distillation, the solution to be open steam distilled should be

Device in which a current of air separates particles with different sedimentation velocities.

The osmotic pressure of a solution containing a 0.20 g mol NaCl/1000 g water at 25ºC is

It is essentially the ratio of buoyancy forces to viscous forces.

In a plate and frame filter press, the rate filtration is directly proportional to the

A vapor whose partial pressure is greater than its equilibrium vapor pressure at a given temperature is called

The rate of evaporation at a given operating temperature in an evaporator is more when

A model turbine, diameter 380 mm, develops 9 kW at a speed of 1500 rpm under a head of 7.6 m. A geometrically similar turbine 1.9 m in diameter will operate at the same efficiency under a 14.9-m head. What power can be expected?

Grindability index of a coal is 100. It implies that the

A mixture of 50% by weight ethanol and 50% by weight water is distilled at 1 atm to give a distillate containing 85 wt % ethanol and a bottoms product containing 3 wt % ethanol. The feed is introduced as saturated liquid at a rate of 453.6 kg/h. The reflux ratio is 1.5. The amount of distillate produced is

The material passing one screening surface and retained on a subsequent surface is called

The separation of a dilute slurry or suspension by gravity settling into a clear fluid and a slurry or suspension by gravity settling into a clear fluid and a slurry of higher solids content is called

The ratio of the internal thermal resistance of a solid to the boundary layer thermal resistance is described by the

Unbound moisture in granular and porous solid, moves through the interstices of the solid by a mechanism involving

A 20% aqueous solution of Na₂CO₃ and 25% aqueous solution of Ca (OH)₂ were reacted to produce caustic soda solution. The precipitate which formed was analyzed to contain 5% H2O, 1% NaOH, 94% CaCO₃. The concentration of NaOH solution produced is ___.

An infinite solid in unsteady state heat conduction is one where

The diameter of Raschig rings used in a packed tower in industry is normally around _____.

A dilute aqueous solution of acetic acid anhydride is to be hydrolyzed at 25 deg C in a single CSTR. The volume of the reactor is 5 liters. The rate of disappearance of the anhydride follows a first-order reaction with half-life of 4.4 minutes. The feed entering the reactor contains 0.00015 g-mols of anhydride per cubic centimeter. The feed rate is 500 cubic centimeters per minute. Find the percent conversion.

The measure of the relative effectiveness of momentum and energy transport by diffusion in the velocity and thermal boundary layers is given by the

In filtration, the finer the filtration medium is ___________ the constant rate period.

A spherical carbon steel storage tank for ammonia has an inside diameter of 30 ft. All joints are butt welded with backing strip. If the tank is to be used at a working pressure of 50 psig and a temperature of 80 deg F, estimate the necessary wall thickness.  Assume no corrosion is necessary, efficiency is 80% and the allowable tensile strength is 13,700 psi.

Which among the gases listed is not transparent to gas radiation?

Find the work done when 3.2 moles of hydrogen expand isothermally and reversibly at 37.6 deg C from 20.8 L to 79.8 L.

Molecular diffusion is caused by ___________.

The Brinkman Number is often used in the analysis of organic liquid flows. This dimensionless number is proportional to viscosity, µ. Derive the Brinkman number if it depends on the viscosity, velocity of flow, V, thermal conductivity, k, and fluid temperature, T.

Nicotine is to be extracted from water using kerosene. If 100 lb of a 2% nicotine solution is extracted once with 200 lb of kerosene, what percent of the nicotine is extracted? (Equilibrium data: Y (lb nicotine/lb kerosene) = 0.90 x (nicotine/lb water)

When the molal latent heat of vaporization of the binary system is very much dependent on concentration, the most appropriate method to use to determine the number of ideal stages is

Water at 83 liters/sec is flowing inside a 6 inch schedule 30 nominal pipe. What is the maximum velocity In ft/s of the water at room temperature?

If 1 L of ethyl alcohol is mixed with 1 L of water at 20C, how many kilograms is the resulting solution?

The Bayer process for purifying bauxite relies upon the

One drier will dry a material from 45% moisture (wb) to 20% moisture (db) from here the material enters another drier where the H2O content is further reduced to give a final product weighing 1000 kg. If the total evaporation from both driers is 800 kg, the moisture of the final product is

A certain reaction has an activation energy of 12.8 kcal/mol. The rate constant is 0.69 mol/cm³ -atm-s at 128.66 °F. What is the value of the specific rate constant at 100 °C in mol/cm³-atm-s?

Which of the following is true regarding Thiele modulus f porous catalyst pellets?

The power requirement of a 3-stage compressor in hp to supply air at 90 °C at a rate of 1200 m³/hr at a total discharge pressure of 400 psig is ___ if the efficiency of the compressor is 65%.

For the reaction . The initial concentrations of both B and C is 0.0019 M while the initial concentration of A is 0.0105 M. What is the time at which the concentration of B is maximum?

A major by-product in the Hall electrometallurgical process for refining aluminum is

Leg support is meant for

For aqueous solutions, the most important variable in natural-circulation evaporators is

A 30° inclined manometer is used to measure the pressure drop between two taps carrying water with 40-in distance inclined by 20°. The manometer fluid is an oil with a specific gravity of 1.92 and the manometer reading is 8 in. What is the pressure difference in psi between the two pipe taps if the manometer tubing is 1/4 in in diameter?

Three parallel branches of PFR’s (A, B, C) are used. Branch A in series is composed of V_A1 = 100 L, V_A2 = 150 L, V_A3 = 200 L; Branch B in series: V_B1 = 50 L, V_B2 = 250 L; and Branch C in series: V_C1 = 100 L, V_C2 = 400 L. If the total flow rate is 1000 L/hr, what is the residence time of V_A3 in minutes?

What depth should a water pipe be buried in wet soil (a = 0.03 ft²/hr) initially at 50ºF for the surrounding soil temperature to remain about 33ºF, if the soil surface temperature suddenly drops to 0ºF and remains at this value for 8 hours?

Wet solid is to be dried from 40% to 10% moisture in 5 hours under CDC. The equilibrium moisture content is 7% and the critical moisture content is 20%. All moisture contents are on dry basis. Calculate the time to dry from 15% to 5% free moisture under the same drying conditions.

How much CaCl₂ • 6H₂O must be dissolved in 100 kg of water at 20ºC to form a saturated solution? The solubility of CaCl₂ at 20ºC is 6.7 gmol anhydrous salt (CaCl₂) per kg of water.

Determine the net heat transfer by radiation between two flat parallel squares A and B 2m x 2m, one exactly above the other, 2m apart.  A is at 300°C with emissivity of 0.9 and B is at 100°C with emissivity of 0.25.

In dehumidification, where the Lewis Number is equal to one, the operating line on the gas-enthalpy-liquid temperature graph

Acetone is to be removed from an air/acetone mixture using a plate column at 1 atm. The mixture enters the bottom of the absorber containing 2% acetone by volume. Pure water is used to remove 95% of the acetone. If the actual liquid flow rate is 1.2 times the minimum required and if the equilibrium relationship is represented by y* = 2.53x, what is the theoretical number of stages?

McCabe-Thiele method, to determine the theoretical number of stages in binary distillation, may be applied with acceptable result if

A sling psychrometer is whirled on a fast spin when measuring the wet bulb temperature of ambient air

Maximum size reduction in a fluid energy mill is achieved by

When the mean free path of a gas is very much greater than the pore diameter, the diffusion mechanism can be regarded as

The pipe size of a pneumatic conveyor to convey plastic pellets with bulk density of 30 lb/ft³ using a blower with a capacity of 600 ft³/min. is

The terminal velocity of a small sphere settling in a viscous fluid varies as the