Separation techniques

Question 1

What is a mixture?

Answer 1

A mixture is made up of components that are not chemically combined.

• Mixtures can be separated by several methods or techniques.

Question 2

What is one major aspect that determines how a mixture will be separated?

Answer 2

The physical properties

Question 3

What are the methods of separation?

Answer 3

Magnetic attraction
Evaporation
Distillation
Separating funnel
Chromatography 
Centrifuge 
Filtration
Crystallization 
Sieving

Question 4

What is the separation method, magnetic attraction, used for?

Answer 4

Magnetic attraction is used to separate a substance that is magnetic from another substance having no magnetic qualities.

Question 5

Applications of magnetic attraction

Answer 5

1. Electromagnets are used to remove steel and iron scraps from a junkyard.
2. In hospitals, magnets are often used to remove iron splinters from patient’s eyes.

Question 6

How is the separation method, Evaporation to dryness used?

Answer 6

Used to separate a dissolved solid( solute) that does not decompose on heating of a solution.

Question 7

What is the procedure used to evaporate a substance?

Answer 7

1. pour the substance into an evaporating dish
2. heat the solution to dryness to evaporate the solvent to dryness, leaving the solute behind.
3. Make the Bunsen burner flame smaller when almost all the solvent has evaporated away to avoid spitting.

Question 8

Applications of Evaporation

Answer 8

1. to dry clothes
2. dry hair
3. obtaining common salt from the sea

Question 9

Crystallization

Answer 9

The process of obtaining a solid that decomposes on heating from its solution.

Question 10

Filtration

Answer 10

Filtration separates a liquid from a solid.

Question 11

What are the components of a filtered substance?

Answer 11

residue- the insoluble solid that remains on the filter paper
Filtrate- the liquid that passed through the filter paper.

Question 12

Applications of filtration

Answer 12

• hair in our nostrils
• air filters in air conditioners
• oil and air filters in cars

Question 13

What is simple distillation?

Answer 13

Simple distillation is the process of separating a pure liquid from a solid-liquid solution.

Question 14

mis·ci·ble

Answer 14

adjective
(of liquids) forming a homogeneous mixture when added together.
“sorbitol is miscible with glycerol”

Question 15

What is Fractional Distillation?

Answer 15

Fraction distillation is the process of separating miscible liquids with different boiling points.

eg. to separate alcohol and water

Question 16

paper chromatography

Answer 16

The process used to separate different components in a liquid mixture.

Question 17

Uses of Paper Chromatography

Answer 17

1. To separate different colored components that make up black ink
2. To detect tiny amounts of drugs or certain other chemicals in urine samples.

Question 18

Centrifugation

Answer 18

• Spin sample very rapidly: denser material goes to the bottom(outside)

Question 19

Applications of Centrifuge

Answer 19

• Is used to separate cream from milk and the butter from crude in diaries at home.

Question 20

Separating funnel

Answer 20

• When two immiscible liquids are mixed together they eventually form layers, if left to stand. The less dense liquid forms a layer above the more dense liquid. Separation of two immiscible liquids using a separating funnel.

Question 21

Sieving

Answer 21

Used to separate coarse from fine parts of loose matter

Question 22

What is straining?

Answer 22

Pour a mainly liquid substance through a porous device or material in order to separate any solid matter.

Question 23

What is Winnowing?

Answer 23

Winnowing is separating the chaff from the grain by the wind.