Chapter 4

Question 1

What is magnetic attraction?

Answer 1

It is a separation technique used to separate magnetic materials from non-magnetic materials. (SOLID TO SOLID

Question 2

What is SUBLIMATION?

Answer 2

a process in which a substance changes from solid to gas without passing through liquid state.

Question 3

What are some substances that can sublime?

Answer 3

OCD + ACIDI
(Oxygen, carbon dioxide + aluminium chloride, dry ice and iodine)

Question 4

What is filtration?

Answer 4

is a technique used to** separate an insoluble solid from the liquid in a solid-liquid mixture.**

Question 5

What is Evaporation To Dryness and Crystallisation

Answer 5

can be used to separate dissolved solids from a solution (soluble solid-liquid mixture)

Question 6

What is simple distillation?

Answer 6

is used to separate a** pure solvent from a solution **(soluble solid-liquid mixture)

Question 7

When can we use Evaporation to dryness and crystallisation and when do we use simple distillation

Answer 7

Evaporation to dryness and crystallisation -> obtain solid
Simple distillation -> obtain liquid

Question 8

What is fractional distillation?

Answer 8

is used to separate a mixture of miscible liquids that have diff. boiling points.

Question 9

What is paper chromotography?

Answer 9

is the technique used to separate small amounts of substances from mixtures by mking use of the fact that diff. substances dissolve to different extents in solvent.

Question 10

under paper chromotogrpahy,

How to calculate Rf value:

Answer 10

Rf value = Distance travelled by the substance / Distance travelled by solvent