Description : __________ diffusion is used for separating the isotopes of methane. (A) Thermal (B) Pressure (C) Concentration (D) Force
Last Answer : (A) Thermal
Description : Molecular diffusion is caused by the (A) Transfer of molecules from low concentration to high concentration region (B) Thermal energy of the molecules (C) Activation energy of the molecules (D) Potential energy of the molecules
Last Answer : (B) Thermal energy of the molecules
Description : The type of liquor circulation system to be ' employed in evaporators (viz. natural or forced circulation) is determined mainly by the __________ of the liquid. (A) Viscosity (B) Density (C) Thermal conductivity (D) Corrosive nature
Last Answer : (A) Viscosity
Description : __________ is the separation technique used for desalination of sea water. (A) Thermal diffusion (B) Reverse osmosis (C) Adsorption (D) Absorption
Last Answer : (B) Reverse osmosis
Description : Diffusion in concentrated solutions differs from that in dilute solutions, because of the change in the __________ with the concentration of the solution. (A) Degree of ideality (B) Viscosity (C) Both 'a '& 'b' (D) Neither 'a' nor 'b'
Last Answer : (C) Both 'a '& 'b
Description : Diffusion co-efficient generally depends upon the temperature, pressure & the nature of the components of the system. Its dimension is not the same as that of the (A) Mass transfer co-efficient (B) Thermal diffusivity (C) Kinematic viscosity (D) Volumetric diffusivity
Last Answer : (A) Mass transfer co-efficient
Description : Analogy between mass and heat transfer is not applicable in case of (A) Same velocity profile or equal eddy diffusivities (B) Thermal or pressure mass diffusion (C) Viscous heating or chemical reaction (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : In case of liquid-liquid binary diffusion, diffusivity of one constituent into another is not dependent on the (A) Temperature and pressure (B) Concentration (C) Nature of the constituents (D) None of these
Last Answer : (D) None of these
Description : The relation among various mass transfer co-efficients (M.T.C) for ideal gases is given by (where, Kc & Km are M.T.C. for equimolar counter diffusion with concentration & mole fraction respectively as the driving ... (C) Kc = Kp . RT = Km . RT/p (D) None of these
Last Answer : (C) Kc = Kp . RT = Km . RT/p
Description : Pick out the wrong statement. (A) The binary diffusivity in liquids is of the order of 10 -5 cm2 /sec (B) Molecular diffusion in solid is much faster than that in liquids ( ... Poiseuille's law, the permeability decreases with increase in temperature for flow of a gas through a given capillary
Last Answer : (B) Molecular diffusion in solid is much faster than that in liquids
Description : A first order reaction A → B occurs in an isothermal porous catalyst pellet of spherical shape. If the concentration of A at the centre of the pellet is much less than at the external surface, the ... A) Diffusion within the pellet (B) Reaction (C) External mass transfer (D) None of the above
Last Answer : (A) Diffusion within the pellet
Description : In the passive diffusion, solute molecules cross the membrane as a result of A- concentration difference B- pressure difference C- ionic difference D- all of these
Last Answer : concentration difference
Description : What is the eventual result of the cellular process of diffusion Describe concentration prior to and at this point?
Last Answer : The eventual result of diffusion is equilibrium.The concentrations prior to this point would be uneven. Thesolutes then diffuse from areas of high solute concentration toareas of low solute concentration. After diffusion, at equilibrium,the concentration will be even in different areas.
Description : Sodium ions are "pumped" from a region of lower concentration to a region of higher concentration in the nerve cells of humans. This process is an example of (A) Diffusion (B) Passive transport (C) Osmosis (D) Active transport
Last Answer : (D) Active transport
Description : Substances insoluble in a membrane are carried across the membrane with the concentration gradient by means of a carrier molecule in a process known as: a) osmosis. b) diffusion. c) active transport. d) facilitated diffusion.
Last Answer : ANSWER: D -- FACILITATED DIFFUSION.
Description : When the ratio of the Grashoff number and to the square of Reynolds number is one, the dominant mechanism of heat transfer is: (A) Free convection (B) Entry length problem in laminar forced ... (developing thermal boundary layer) (C) Mixed convection (both free and forced) (D) Forced convection
Last Answer : (C) Mixed convection (both free and forced)
Description : Pick out the correct statement. (A) 1 kcal/hr.m.°C is equal to 1 BTU/hr. ft.°F (B) In steady state heat conduction, the only property of the substance which determines the ... in the direction of temperature rise (D) In heat transfer by forced convection, Grashoff number is very important
Last Answer : (B) In steady state heat conduction, the only property of the substance which determines the temperature distribution, is the thermal conductivity
Description : Separation of the isotopes of helium for scientific investigations is done by (A) Reverse osmosis (B) Thermal diffusion (C) Leaching (D) Solvent extraction
Last Answer : (B) Thermal diffusion
Description : Forced circulation evaporators are useful for the concentration of viscous, salting and scale forming liquors. Which of the following is a forced circulation evaporator? (A) Long vertical evaporator (B) Horizontal tube evaporator (C) Agitated film evaporator (D) Calandria vertical tube evaporator
Last Answer : (C) Agitated film evaporator
Description : Pick out the wrong statement. (A) The Reynolds analogy for mass transfer is given by Lewis relation and is applicable, when Schmidt number is one (B) Sherwood number for flow in pipes can be expressed ... flux of a component A in binary mixture of A and B is given by - Dab'.dCA/dz
Last Answer : (C) According to film theory for equimolar counter diffusion, the mass transfer coefficient is given by DAB(B)P - 3, Q - 2
Description : Bulk diffusion in catalyst pore __________ with increase in pressure. (A) Increases (B) Decreases (C) Remains unchanged (D) Increases exponentially
Last Answer : (B) Decreases
Description : Separation of __________ employs gaseous diffusion process. (A) N2 and O2 from air (B) Isotopes of uranium (C) Isotopes of helium (D) SO2 and air
Last Answer : (B) Isotopes of uranium
Description : 'Utilities' in a chemical process plant includes compressed air, steam, water, electrical power, oxygen, acetylene, fuel gases etc. Utility costs for ordinary chemical process plants ranges roughly from __________ percent of the total product ... 1 to 5 (B) 10 to 20 (C) 25 to 35 (D) 35 to 45
Last Answer : (B) 10 to 20
Description : Diffusion due to thermal motion is called a. dilation b. infusion c. effusion d. dispersion
Last Answer : effusion
Description : Stage efficiency in a leaching process depends on the (A) Time of contact between the solid and the solution (B) Rate of diffusion of the solute through the solid and into the liquid (C) Both (A) and (B) (D) Vapour pressure of the solution
Last Answer : (C) Both (A) and (B)
Description : Which of the following best describes what a concentration camp isA. A place to concentrate on hard tasks B. A place to take napsC. A place where people were forced to work and often dieF. A fun spot to fo far a vacation?
Last Answer : The Devils Arecmutic
Description : $ Positive diffusion occurs against the concentration gradients. ! Osmosis does not require a semi-permeable membrane.
Last Answer : $ Positive diffusion occurs against the concentration gradients. ! Osmosis does not require a semi-permeable ... D. If both As and R are wrong.
Description : In facilitated diffusion do molecules move down concentration gradient?
Last Answer : What is the answer ?
Description : Without saturation of transport proteins and under same concentration gradient how can the speed of simple diffusion be compared to the speed of facilitated diffusion ?
Last Answer : The action of facilitator proteins in facilitated diffusion makes this type of diffusion faster than simple diffusion under equal concentration gradients of the moved substance.
Description : How does the intensity of facilitated diffusion vary in relation to the concentration of the moved substance ?
Last Answer : What is the limiting factor? Likewise simple diffusion facilitated diffusion is more intense when the concentration gradient of the substance increases and less intense when the gradient lessens. In ... which the maximum transport capacity of the substance across the membrane is achieved.
Description : How does the intensity of simple diffusion vary in relation to the concentration gradient of the moved substance ?
Last Answer : The higher the concentration gradient of a substance the more intense its simple diffusion will be. If the concentration gradient diminishes the intensity of simple diffusion diminishes too.
Description : In the resting state of the neural membrane, diffusion due to concentration gradients, if allowed, would drive (a) K+ into the cell (b) K+ and Na+ out of the cell (c) Na+ into the cell (d) Na+ out of the cell.
Last Answer : c) Na+ into the cell
Description : The movement of ions against the concentration gradient will be (a) active transport (b) osmosis (c) diffusion (d) all of the above.
Last Answer : (a) active transport
Description : The is used to determine an antibiotic‘s minimal inhibitory concentration (NEC). a. Ames test b. tube dilution method c. agar disk diffusion method d. Kirby-Bauer test
Last Answer : b. tube dilution method
Description : Why is the frequency of carbohydrate intake more important than the quantity: A. Low number of streptococcus mutans B. Hetero formation is better at low sugar concentration C. Homo formation is better at high sugar intake D. Restricted diffusion of acid through plaque
Last Answer : D. Restricted diffusion of acid through plaque
Description : 'Diffusion hypoxia’ is likely to occur only after use of nitrous oxide because it: A. Is a respiratory depressant B. Has low blood solubility and is used in high concentration C. Is a very potent anaesthetic D. Interferes with diffusion of oxygen into the tissues
Last Answer : B. Has low blood solubility and is used in high concentration
Description : Reverse osmosis is also called (A) Dialysis (B) Electrodialysis (C) Diffusion (D) Ultra-filtration
Last Answer : (D) Ultra-filtration
Description : Pick out the wrong statement pertaining to the cooling towers. (A) In case of induced draft cooling tower, the fan is placed at the top of the tower (B) Effectiveness of ... Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature
Last Answer : (D) Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature
Description : Supercharging is the process of a. supplying the engine with air at a density greater than the density of the surrounding atmosphere b. providing forced cooling air c. injecting excess fuel d. raising the exhaust pressure
Last Answer : ANSWER a. supplying the engine with air at a density greater than the density of the surrounding atmosphere
Description : For gases, the thermal conductivity increases with temperature rise. For liquids, with increase in concentration, its thermal conductivity generally (A) Decreases (B) Increases (C) Remains unchanged (D) Increases exponentially
Last Answer : (A) Decreases
Description : . If Prandtl number is greater than the Schmidt number, then the (A) Thermal boundary layer lies inside the concentration boundary layer (B) Concentration boundary layer lies inside the thermal boundary ... (D) Hydrodynamic (i.e., momentum) boundary layer is thicker than the other two
Last Answer : (A) Thermal boundary layer lies inside the concentration boundary layer
Description : Pick out the wrong statement. (A) When the concentration difference for the mass transfer becomes zero at the bottom of the gas absorption tower, then the upper end of the operating line touches the ... fixed gas flow rate, the slope of the operating line decreases, in case of gas absorption process
Last Answer : (C) The operating line lies above the equilibrium curve in case of a gas desorber
Description : If fuel and air are mixed ahead of the burner, it is called a/an __________ burner. (A) Premix (B) Outside mixing type (C) Rotary (D) Diffusion
Last Answer : (A) Premix
Description : Boiling point of a solution according to Duhring's rule is a linear function of the __________ of water. (A) Boiling point (at the same pressure) (B) Viscosity (C) Density (D) Thermal conductivity
Last Answer : (A) Boiling point (at the same pressure)
Description : In case of wet spinning of polymers, the polymer solution is forced through spinnerates into, a coagulating bath to give a filament form. Wet spinning is not used in case of the __________ fibres. (A) Viscose rayon (B) Acrylic (C) Polyvinyl acetate (D) Saturated polyeste
Last Answer : (D) Saturated polyeste
Description : In case of dry spinning of polymers, the polymer solution in a volatile solvent is forced through the spinnerates into a warm air chamber, where the solvent evaporates leaving behind the polymer in the filament ... is used for __________ fibres. (A) Polythene (B) PVC (C) Rayon (D) Polyvinyl acetate
Last Answer : (B) PVC
Description : When the temperature and humidity of air is low, we usually use __________ draft cooling tower. (A) Natural (B) Forced (C) Induced (D) None of these
Last Answer : (A) Natural
Description : Nusselt number (for forced convection heat transfer) is a function of the __________ number. (A) Prandtl (B) Reynolds (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
Description : Heat transfer by __________ may not necessarily require the presence of a medium. (A) Conduction (B) Natural convection (C) Forced convection (D) Radiation
Last Answer : (D) Radiation
Description : Mode of heat transfer in which the fluid moves under the influence of changes in fluid pressure produced by external work is called (A) Radiation (B) Natural convection (C) Forced convection (D) Conduction
Last Answer : (C) Forced convection