12.4 Separation Techniques

What is the purpose of using a solvent in purification?

• To dissolve all substances

• To separate solids based on solubility

• To mix substances

• To evaporate substances.

Filtration can be used to remove unwanted substances from a ______.

• Solution

• Suspension

• Gas

• Crystal

Which of the following is an example of a crystalline substance?

• Water

• Sand

• Salt

• Oil

What happens to the solvent in the process of obtaining sugar from a filtrate?

• It dissolves

• It evaporates

• It crystallizes

• It solidifies

In crystallisation, if a liquid solution is allowed to cool slowly, the crystals grown will be ______ than those formed from rapid cooling.

• smaller

• larger

• the same size

• non-existent

What is distillation?

• A method to separate solids

• A method to separate substances with different boiling points

• A method to freeze liquids

• A method to mix liquids

Fractional distillation is used to separate a mixture of liquids with different ______.

• colors

• boiling points

• densities

• solubilities

Which process uses a round bottomed flask connected to a long tube called a condenser?

• Crystallisation

• Simple distillation

• Decanting

• Filtration

True or False: Fractional distillation and simple distillation use the same apparatus in a school laboratory.

• True

• False

What is the main difference between simple and fractional distillation?

• The use of a condenser

• The use of glass beads

• The type of flask used

• The temperature used