Seperating Mixtures

Question 1

Physical change

Answer 1

No change in partials, just the particle arrangement and energy, easy to reverse e.g. mixing water and salt

Question 2

Chemical change

Answer 2

A chemical reaction takes place and a new substance is formed, very difficult to reverse e.g. burning a match

Question 3

Durning a chemical reaction

Answer 3

The atoms rearrange to form a new substance, might be seen by temperature change, colour change and light being admitted or bubbles

Question 4

Law of conservation of mass

Answer 4

Matter can be changed from one form to another. Durning physical and chemical changes, there is no overall change of mass.

Question 5

Distillation

Answer 5

Used to separate two liquids with different boiling points such as alcohol (boils at 78°) and water (boiled at 100°). Also used to separate a soluble solid form a liquid (e.g. seawater) to give a pure sample of each

Question 6

Chromatography

Answer 6

Used to separate a mixture of dissolved substances in a solution. E.g. the different colours in a black marker