4. Why is HETP larger than for staged devices? Explanation: To avoid back-mixing, HETP is larger for staged devices thus packed columns are used only when few stages are required.

What is the major problem in settlers?

The first settlers of Jamestown endured the problems of hostile Indians, starvation, and poor leadership and government. Jamestown was the second English Colony in the New World (Roanoke being the first) and the Indians attacked the settlers within 3 days of arrival in May of 1607.

What is the use of ether layer?

What is the use of ether layer? Explanation: Since ether is a non-polar compound, its layer is used to separate organic impurities. Explanation: A mobile phase has to flow and hence it should not be a solid.

Which law is used in solvent extraction?

1) SOLVENT EXTRACTION

Extractions made from solvents are based on the "law of disintegration of Nerst". Distribution law or the Nernst's distribution law gives a generalisation which governs the distribution of a solute between two non miscible solvents.

What type of agitator is rotating disk agitator Mcq?

Explanation: The disc turbines are the type of agitators that consists of a series of rectangular vanes arranged in a vertical plane or fashion around the circumference of the discs. The disc turbines rotate at a very high speed. 7.

Packed Column Design

33 related questions found

Which of the following is not an adsorbent?

1. Which of the following is not an adsorbent? Explanation: A sponge will absorb or take in water from another area and put it inside of itself. A dry sponge can hold more water than a wet sponge is closer to saturation and as such cannot hold more water.

What do you mean by impeller flooding Mcq?

Explanation: Impeller flooding is said to occur; this means that the gas-handling capacity of the stirrer is smaller than the amount introduced. ... Explanation: In a non-coalescing liquid, the bubbles remain close to the size produced at the back of the cavities.

Which solvent is lighter than water?

An aqueous sample solution containing the analytes was transferred into the device on top of the glass filter, and a lighter-than-water extraction solvent (ChCl:pivalic acid) was placed under the glass filter.

For which solution distribution law is true?

The distribution law is valid only for the ratio of concentrations of similar molecular species in the two solvents.

What type of mixtures can be separated by solvent extraction?

Liquid–liquid extraction (LLE), also known as solvent extraction and partitioning, is a method to separate compounds or metal complexes, based on their relative solubilities in two different immiscible liquids, usually water (polar) and an organic solvent (non-polar).

What two solvents could be used in a successful extraction?

The most common pair of extraction solvents used is diethyl ether (often referred to as simply 'ether') and water.

What is solvent extraction technique?

Solvent extraction is a process in which compounds are separated based on their relative solubilities. This treatment method involves using a solvent - a fluid that has the ability to dissolve another substance. ... Solvent extraction is used to separate hazardous contaminants from sludge and sediments as well.

How does packing the column help?

How does packing the column help? Explanation: The packing columns minimize the axial dispersion and help by increasing the mass transfer by breaking the large droplets thus increasing interfacial area.

What does solid liquid separation not involve?

What does the solid-liquid separation operation don't involve? Explanation: The solid-liquid separations always involve gravity sedimentation, filtration and centrifugation. Magnetic separation is not involved.

How does centrifuge extraction work?

A centrifugal extractor—also known as a centrifugal contactor or annular centrifugal contactor—uses the rotation of the rotor inside a centrifuge to mix two immiscible liquids outside the rotor and to separate the liquids in the field of gravity inside the rotor.

What is maceration extraction Mcq?

Clarification: A maceration extraction consists of preserving contact between the plant and liquid for a period of time. It is an extractive technique that is conducted at room temperature where plant is immersed in a liquid like water, oil, alcohol.

How distribution law is useful in solvent extraction?

Distribution law or the Nernst's distribution law gives a generalisation which governs the distribution of a solute between two non miscible solvents. This law was first given by Nernst who studied the distribution of several solutes between different appropriate pairs of solvents.

What is distribution law its application and limitations?

When a solute is shaken with two non-miscible solvents, at equilibrium both the solvents are saturated with the solute. ... we can write the distribution law as C1/C2 = S1/S2 = KD where S1 and S2 are the solubilities of the solute in the two solvents.

What is distribution law where it is applicable?

This law is only valid if the solute is in the same molecular form in both the solvents. Sometimes the solute dissociates or associates in the solvent. In such cases the law is modified as, D(Distribution factor)=concentration of solute in all forms in solvent 1/concentration of solute in all forms in solvent 2.

Is ice lighter than water?

In practical terms, density is the weight of a substance for a specific volume. The density of water is roughly 1 gram per milliliter but, this changes with temperature or if there are substances dissolved in it. Ice is less dense than liquid water which is why your ice cubes float in your glass.

Will carbon tetrachloride float on water?

Density of carbon tetrachloride at ambient conditions is approximately 1.5 g/ml, so for a given volume carbon tetrachloride has a higher mass than water. So when combined the carbon tetrachloride would sink below the water.

Is carbon tetrachloride is lighter than water?

Carbon tetrachloride (Carbon tet) is a non-flammable colorless liquid with a heavy, sweet odor. Carbon tet evaporates quickly and is heavier than water. ...

What is agitator in reactor?

An agitator is a device which is used to import motion in the form of stirring to the liquids or semi solids. The agitator is a device which contains a shaft and an impeller/propeller. The shaft is connected to the gear box and the assembly is driven by motors using electricity.

What is Fick's law applicable to Mcq?

3. What is Fick's law applicable to? Explanation: In single-phase systems, the rate of mass transfer due to molecular diffusion is given by Fick's law of diffusion, which states that mass flux is proportional to the concentration gradient.

Why the shake flask is not continuously preferred?

5. Why the shake flask is not continuously preferred? Explanation: Shake flasks are usually subject to media evaporative loss in warmer culture environments, typically 10% of volume per 24 hr at 37°C.