Q. In plate evaporator, the heat transfer coefficient is high in spite of low residence time because _____

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Q. Shifting of a pair of ripened apples from the store house to the vegetable cart is called mass transfer.

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Q. Statement 1: When alcohol is allowed to move from chamber A to chamber B when a barrier between them is removed, it is called multi phase diffusion.
Statement 2: When oxygen is made to diffuse into the water, it’s called continuous molecular diffusion.

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Q. Velocity gradient is the main driving force in mass transfer.

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Q. Statement 1: A phase boundary exists between alcohol and oxygen.
Statement 2: Phase boundary varies with agitation. It is inversely proportional to the amount of agitation provided.

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Q. A phase boundary between alcohol and water exists.

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Q. Statement 1: Diffusion is faster than convective mass transfer.
Statement 2: Mass transfer is proportional to the area of contact.

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Q. Statement 1: Resistance is inversely proportional to the inter-facial area.
Statement 2: The inter-facial area of a body is the area of the dispersed phase in a unit volume of the vessel.

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Q. Ratio of equilibrium concentrations of solute A in liquid phase and gas phase i.e. CAL* and CAg* respectively is α. α is called _____

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Q. Statement 1: Diffusion of gas component through the resistive film to the bulk of the liquid is the rate determining step.
Statement 2: Diffusion of gas component through the gas-liquid inter-phase is the rate determining step.

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Q. In a packaging of dry grapes, the packaging material is made of polyethylene. The dry grapes have certain moisture content. Which of the following is true with respect to the diffusion of certain amount of moisture through the packing?

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Q. Statement 1: Concentration is a product of diffusivity and solubility.
Statement 2: Permeability coefficient in case of food packaging can be written as product of partial pressure and solubility using Henry’s law.

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Q. The existence of a thick constant film between two phases is a proposal by which of the following theories?

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Q. Statement 1: Penetration theory states that mass transfer coefficient is directly proportional to diffusivity coefficient which was later proved wrong.
Statement 2: Penetration theory states that mass transfer is based on unsteady mass transfer.

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Q. Statement 1: In film theory, mass transfer coefficient is proportional to D¹/².

Statement 2: Penetration theory states that all elements are exposed at the same time which is unrealistic.

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Q. Which theory proposes that the film is continuously getting renewed and replaced by the bulk liquid?

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Q. Statement 1: KLa is measured together and not separately.

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Q. Which of the following is not a measuring technique of KLa?

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Q. Which of the following is also called Oxygen balancing method?

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Q. Sherwood number is _____

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