What does filtration separate?

Filtration separates an insoluble solid from a liquid or solution. The solid remains on the filter paper as the residue , while the liquid passes through as the filtrate .

In crystallisation, the solution is heated to allow the .......... to evaporate, then cooled slowly so that .......... grow as solubility decreases.

In crystallisation, the solution is heated to allow the solvent to evaporate, then cooled slowly so that crystals grow as solubility decreases.

Why is fractional distillation preferred over simple distillation to separate ethanol from water?

Fractional distillation is preferred because ethanol and water are miscible liquids with different boiling points. The fractionating column allows repeated condensation and re-evaporation, so the more volatile liquid is collected first, giving a higher degree of purity.

A pure substance melts at a .......... temperature, whereas a mixture melts over a .......... of temperatures.

A pure substance melts at a sharp temperature, whereas a mixture melts over a range of temperatures.

True or False? Impurities raise the melting point of a substance.

False. Impurities lower the melting point of a substance and cause it to melt over a range of temperatures rather than at a sharp, fixed point.

In simple distillation, the liquid .......... on heating and the vapour passes through a .......... , where it cools and condenses into a pure liquid.

In simple distillation, the liquid evaporates on heating and the vapour passes through a condenser , where it cools and condenses into a pure liquid.

How can you test whether a solution is saturated during crystallisation?

To test whether a solution is saturated , dip a clean, dry, cold glass rod into it. If crystals form on the rod when removed, the solution is saturated.

Fractional distillation separates two .......... liquids with close boiling points using a fractionating .......... , which allows repeated condensation and re-evaporation.

Fractional distillation separates two miscible liquids with close boiling points using a fractionating column , which allows repeated condensation and re-evaporation.

O LevelChemistryCambridge (CIE)Flashcards12. Experimental Techniques & Chemical Analysis12.4 Separation & Purification

12.4 Separation & Purification (Cambridge (CIE) O Level Chemistry): Flashcards

Exam code: 5070

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What does filtration separate?

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What does filtration separate?
Filtration separates an insoluble solid from a liquid or solution. The solid remains on the filter paper as the residue, while the liquid passes through as the filtrate.
In crystallisation, the solution is heated to allow the .......... to evaporate, then cooled slowly so that .......... grow as solubility decreases.
In crystallisation, the solution is heated to allow the solvent to evaporate, then cooled slowly so that crystals grow as solubility decreases.
Why is fractional distillation preferred over simple distillation to separate ethanol from water?
Fractional distillation is preferred because ethanol and water are miscible liquids with different boiling points. The fractionating column allows repeated condensation and re-evaporation, so the more volatile liquid is collected first, giving a higher degree of purity.
A pure substance melts at a .......... temperature, whereas a mixture melts over a .......... of temperatures.
A pure substance melts at a sharp temperature, whereas a mixture melts over a range of temperatures.
True or False?
Impurities raise the melting point of a substance.
False.
Impurities lower the melting point of a substance and cause it to melt over a range of temperatures rather than at a sharp, fixed point.
In simple distillation, the liquid .......... on heating and the vapour passes through a .........., where it cools and condenses into a pure liquid.
In simple distillation, the liquid evaporates on heating and the vapour passes through a condenser, where it cools and condenses into a pure liquid.
How can you test whether a solution is saturated during crystallisation?
To test whether a solution is saturated, dip a clean, dry, cold glass rod into it. If crystals form on the rod when removed, the solution is saturated.
Fractional distillation separates two .......... liquids with close boiling points using a fractionating .........., which allows repeated condensation and re-evaporation.
Fractional distillation separates two miscible liquids with close boiling points using a fractionating column, which allows repeated condensation and re-evaporation.

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