Separation Techniques - Form 2 Integrated Science

Comprehensive flashcards covering filtration, paper chromatography, and fractional distillation based on the Form 2 Integrated Science notes.

What is the primary purpose of filtration in a laboratory setting?

To separate an insoluble solid from a liquid.

Why is filtration unable to separate a soluble solid, such as salt or sugar, from water?

Dissolved particles are small enough to pass straight through the microscopic holes in the filter paper.

In the context of filtration, what is the definition of a "Mixture"?

The combination of the solid and liquid before they are separated, such as muddy water.

What is the difference between the "Residue" and the "Filtrate" in filtration?

The Residue refers to the solid particles trapped in the filter paper, while the Filtrate is the clean, clear liquid that passes through and is collected below.

How do water treatment facilities use filtration for water purification?

They pass reservoir water through thick beds of sand and gravel to filter out floating dirt and organic debris.

How does Paper Chromatography separate a mixture of soluble substances?

It works because different substances dissolve better in a solvent and move up the chromatography paper at different speeds.

During paper chromatography, why must the liquid level be kept below the pencil baseline?

To ensure the ink spot does not wash away into the liquid.

What determines how fast and far a dye travels up chromatography paper?

Dyes that are highly soluble in the solvent travel the fastest and furthest.

Why is a pencil used instead of a regular ink pen to draw the baseline in chromatography?

A regular ink pen line would dissolve in the solvent and separate, ruining the experiment.

How is paper chromatography applied in the field of forensics?

It is used to analyze ink samples from crime scenes, such as forged checks, to match them to a suspect's pen.

What is the specific use for Fractional Distillation?

To separate a mixture of two or more miscible liquids that are completely mixed together based on their differing boiling points.

What component in fractional distillation allows liquids with very close boiling points to be separated perfectly?

The fractionating column filled with glass beads.

What happens to higher-boiling-point liquids when they enter the fractionating column?

Their vapors condense early on the cool glass beads and drip back down into the distillation flask.

What is the function of the Liebig Condenser in fractional distillation?

It utilizes a jacket of cold water to rapidly cool gas down and convert it back into a pure liquid.

What is the term for the pure liquid collected at the end of the distillation process?

The distillate.

How is crude oil processed in industrial applications of fractional distillation?

It is separated into useful products such as petrol, diesel, kerosene, and jet fuel within massive fractionating towers.

How is pure medical oxygen produced for use in hospitals?

Liquid air is fractionally distilled to separate out the pure oxygen gas.