Separating Mixtures

Name:____________________________________Class:_________

Mixtures are not a chemical reaction._ _ _ _ _ _ _ _ are formed when two or more substances are combined. The _ _ _ _ _ _ _ _ _ are often spread evenly or _ _ _ _ _ _ _ _ _ throughout the mixture, but the particles can usually be _ _ _ _ _ _ _ _ _ by filtration or other methods. The particles may be _ _ _ _ _ _, _ _ _ _ _ _ _, or _ _ _ _ _. There are 3 kinds of mixtures.. The first is a _ _ _ _ _ _ _ _ mixture. This is when the particles of a mixture are evenly spread through a mixture, such as salt mixed in water. The second is an _ _ _ _ _ _ _ _ _ _ mixture. This is when particles are not spread evenly throughout the mixture., such as sand in water. The third kind is an _ _ _ _ _ _ _ _. This is a mixture of two liquids in which the particles of the liquids are evenly distributed, such as dish soap in water.

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Directions: Match the words with the big ideas by writing the letter beside the idea. Use the same words in the short article below. Use key words and phrases from the article below to help. you.

A

blocks

B

A

C

D

E

F

G

H

I

J

solid

liquid

particles

gas

mixtures

separated

immiscible

emulsion

dissolved

miscible

To pull two or more things apart

A mixture where a solid dissolves in a liquid

Hard and firm

A mixture where a solid doesn’t dissolve in a liquid

A tiny piece of anything

A wet substance

To divide into parts

Two or more things mixed together

A substance like air

A mixture of 2 liquids that don’t dissolve

1. Miscible mixtures

Example: salt in water – the salt dissolves in the water

2. Immiscible mixtures

Example: sand in water – the sand sinks to the bottom

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Boys and girls,

Did you know that mixtures are not a

chemical reaction? Mixtures are formed

when two or more things are combined.

You can mix a solid with a liquid, liquid with

a liquid, solid with a solid and gas with a

gas.

3. Emulsions

Example: vegetable oil in water – the oil mixes then floats to the top

Unscramble the words to find the secret sentence.

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Use a plastic cup, spoon, magnifying glass, salt, pepper, vegetable oil

and water to look at the 3 different kinds of mixtures.

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1.

3. 4.

2.

Step 1. Put about 5cm of

water into the plastic cup.

Step 2. Put one spoon of salt

into the cup of water.

Step 3. Stir until the salt is

dissolved in the water.

Step 4. Study the mixture

with a magnifying glass.

5.

Step 5. Draw the experiment

in the box and answer the

questions.

Salt mixture

1. Can you see any grains of salt on the bottom of the cup or did it dissolve

completely in the water? ___________________________________________

2. Can you see any un-dissolved grains of salt in the water or is the water clear?

________________________________________________________________

3. Stir one more teaspoon of salt into the cup. Did all of the salt dissolve in the

water? __________________________________________________________

4. Can you see any salt on the bottom of the cup or in the water?

___________________________________________________________________

5. Is the water clear or cloudy? _________________________________________

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Step 7. Stir the pepper and

salt mixture.

7. 6.

Step 6. Add some black

pepper to the cup.

8.

Step 8. Draw the experiment

in the box and answer the

questions.

Pepper and Salt mixture

1. Does the pepper dissolve into the water? ______________________________

2. What do the flakes of pepper do in the water? __________________________

3. Describe the difference between the reaction of salt and pepper when stirred

into the water. ____________________________________________________

_________________________________________________________________

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10. 9.

Step 9. Put some vegetable

oil into the mixture and stir.

Step 10. Draw the experiment

in the box and answer the

questions.

Pepper, Salt and Vegetable oil mixture

1. Does the vegetable oil spread throughout the water? ____________________

2. Can you see the vegetable oil in the water? ____________________________

3. Put your finger into the mixture. Is the vegetable oil spread throughout the

water? ___________________________________________________________

4. What happened to the pepper when the vegetable oil was added to the

mixture? _________________________________________________________

Extension

Let the oil settle to the top again.

Stir the fluids 15 times.

Time how many minutes and seconds it takes for the oil to settle on top of the water.

________________ minutes ________________ seconds

Look at the table of everyday items. Put a cross in the correct box if it is a

MISCIBLE, IMMISCIBLE or EMULSION.

miscible

immiscible

emulsion

cola

dish soap

coffee

salt water

milk

oil

salad dressing

lemon juice

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Use salt, flour, water, food coloring, bowl, cream of tartar and hot

plate to make some fun play dough.

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5. 4.

3. 2. 1.

Step 1. Put 100g of salt and

flour into a bowl. Add 4

teaspoons of cream of

tartar. Mix well.

Step 2. Add food coloring to

100ml of water and stir.

Step 3. Add the colored

water to the mixture and stir

it until you can’t see any

flour.

Step 4. Put the bowl onto

the hot plate. And stir until it

turns into thick dough.

Step 5. Put the dough on to

a dish and let it cool.

1. Paper Chromatography

This method is often used in the food industry. It is used to identify chemicals

(coloring agents) in foods or inks. For example, if a scientist wants to know

how many substances are in a particular blob of ink, paper chromatography

can be used.

2. Filtration

This is a more common method of separating an insoluble solid from a liquid.

An example of such a mixture is sand and water. Filtration is used in water

treatment plants, where water from rivers are filtered to remove solid

particles.

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Boys and girls,

Did you know that most mixtures can be

separated? The kind of separation method

depends on the kind of mixture it is. Let’s

look at some common separation methods.

3. Evaporation

Evaporation is great for separating a mixture (solution) of a soluble solid and

a solvent. The process involves heating the solution until the solvent

evaporates (turns into gas) leaving behind the solid residue.

4. Distillation

This method is best for separating a liquid from a solution. In a way, the

concept is similar to evaporation, but in this case, the vapor is collected by

condensation. For example, if you want to separate water from a salt solution,

simple distillation would be great for this.

5. Magnetism

Magnetism is ideal for separating mixtures of two solids with one part having

magnetic properties. Some metals like iron, nickel and cobalt have magnetic

properties whiles gold, silver and aluminum do not. Magnetic elements are

attracted to a magnet.

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6. Separating funnel

In this technique, two liquids that do not dissolve very well in each other

(immiscible liquids) can be separated by taking advantage of their unequal

density. A mixture of oil and water, for example, can be separated by this

technique.

Empty out the solids that are in your bag. Draw your mixture.

Now, separate your mixture into the different kind of solids.

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Across

1. Something which has particles close together

8. Mixture where two liquids mix and then separate

10. Something which has particles moving quickly everywhere

11. Method of separating a mixture starting with E

14. two pull two things apart

Down

2. Method of separating a mixture starting with D 9. Mixture where a solid or liquid dissolves

3. Mixture where a solid sinks to the bottom of a liquid 12. Method of separating a mixture starting with M

4. When two or more things are mixed together 13. A tiny piece of anything

5. Method of separating a mixture starting with F

6. Something which has particles loosely together

7. When a liquid or solid disappears in another liquid

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Use a magnet, plastic wrap, iron filings, salt, filter paper, sand hot

plate, water and pot to separate three solids.

Before we begin this experiment we need to look at some important information. In

this experiment, we will use three solids, all with different characteristics.

1. Iron is a magnetic solid which doesn't dissolve in water.

2. Salt is a non-magnetic solid which does dissolve in water.

3. Sand is a non-magnetic solid which doesn't dissolve in water.

Material

State

Magnetic

Dissolve in water

Iron

Salt

Sand

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1. 2. 3.

Step 1. Wrap a magnet in

plastic wrap. Move it

through the mixture of the 3

solids

Step 2. Put the iron filings in

a pile on the plate.

Step 3. Put the remaining

solids into a beaker and

add 50ml of water.

What happened? _______________________________________________________

______________________________________________________________________

______________________________________________________________________

______________________________________________________________________

______________________________________________________________________

Draw three pictures in the boxes showing the three processes used to separate the

mixture.

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7.

6. 5. 4.

Step 7. Place the pot on the

hot plate and wait till the

water has evaporated.

Step 6. Put the sand onto

the plate with the iron

filings.

Step 5. Using a funnel filter

the mixture through some

filter paper into a bowl.

Step 4. Stir the mixture.

Step 8. Put the salt onto the

plate.

7.

Magnetic Filtration Evaporation

g d d d j d m h j q p t w r w v m m d f

i a i g e i i t d f d i u q i l s a i y

f q s s x t a s i z z u a z v b i g l e

r k i t t o a l s l y w q t p n t n o c

q l u d l i t r r o q w z n o i e e s a

c r e f f r l i a f l w e i z m n t e n

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s t l t n f b c a e e c e n h i a c p q

o b i p x u i i l t a s i i o s m p v d

l o e s c k f b p e i r o e i c v q s s

n u s e l c i t r a p o k p s i h u z h

o g e e v c a l i i j i n p c b q b e h

n m b p s c a e m u l s i o n l k p l n

m q v i c c t u n u p w q r r e t d b g

h z m j i w q f v f v m w y j r b j l x

j r a m t k c m q e r i p x u g f f s h

u l e j n v k l q t e t b v i s f i e i

a h c o e q e t q n u j s r l b q e p z

c e v a p o a r a t i o n a w d r g n m

s i n k h z x q w a n x e j e g i m d n

chemical reaction dissolve distillation emulsion

evaporation filtration float funnel gas

immiscible liquid magnetic magnetism

mixture particles separated sink solid

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