1. Mixtures, Elements and Compounds
A Matter of Fact
Mixtures, Elements and 
Compounds

2. Mixtures, elements, compounds
Scientists like to classify things.
One way that scientists classify matter is by 
its composition.
Ultimately, all matter (anything that takes up space) can be classified as 
mixtures, elements and compounds.

3. Why isn’t it a good idea to classify matter by its phases?
Because one kind of substance can exist in more 
than one phase – such as H20. And matter changes phases rather easily.  

4. Why isn’t matter classified 
according to its physical 
characteristics, such as color?
Scientists wouldn’t find it very useful to group 
gold, sunflowers, and the sun together.

5. Scientists ask themselves these questions:
Is the matter uniform (the same) throughout?

Can it be separated by physical means?
Can it be separated by chemical means?

6. By asking these questions scientists can classify 
matter into:
Elements – simplest form of pure substance. They cannot be broken into anything else by physical or chemical means.
Compounds – pure substances that are the unions of two or more elements. They can be broken into simpler substances by chemical means.
Mixtures – two or more substances that are not chemically combined with each other and can be 
separated by physical means. The substances in a 
mixture keep their individual properties.
Solutions – a special kind of mixture where one substance 
dissolves in another.

7. Can it be separated by physical means?
If the answer is no, the matter is a pure 
substance.

An element
Or a compound

8. Elements Elements are the simplest pure substance.
An element can not be changed into a simpler substance by 
heating or any chemical process.
The smallest particle of an element that has the 
properties of that element is called an atom.
An atom is the basic building block of matter.
There are more than one hundred known elements 
in the universe listed on the periodic table of 
elements.
These elements combine in such a way to create millions of 
compounds.

9. Elements All elements are made of atoms.
Atoms of the same 
element are alike.
Atoms of different 
elements are 
different.

10. Element

11. Compounds Compounds are also pure substances.
But compounds are 
made from more than 
one element.
Water is a compound.
Water can be broken 
down into simpler 
substances – hydrogen 
and oxygen.

12. Compounds
A compound is a pure substance composed 
of 2 or more elements that are chemically 
combined.

13. Hydrogen (H) + Oxygen (O)
Examples of Compounds
Compounds contain elements
The elements combine + lose their original properties
Compounds CAN be separated by chemical means
The elements combine in specific ratios
Sodium (Na) +
Chlorine (Cl)
NaCl
Hydrogen (H) + Oxygen (O)
H2O
Carbon (C) + Oxygen (O)
CO2

14. Mixtures
A mixture is a combination of 2 or more 
substances that are not chemically 
combined.

15. Examples of Mixtures Properties of Mixtures:
chicken noodle soup
salad
pizza
Properties of Mixtures:
Each substance in a mixture keeps its identity
You can physically separate them
They also contain elements, compounds, or both
And they can be formed using any ratio of
components

16. Mixtures may be homogeneous or
heterogeneous
The prefix “homo” indicates the same
Homogeneous mixtures have the same 
appearance and properties throughout the 
mixture
The prefix “hetero” indicates difference
Heterogeneous mixtures consist of visibly 
different substances

18. Examples of Heterogenous mixtures
Sand and pebbles
Oil and water
Powdered iron and powdered sulfur

20. Homogeneous Mixtures
Milk, toothpaste, and mayonnaise are mixtures.

22. Comparing Elements, Compounds & Mixtures
What are they made 
up of?
Can they be broken 
down? If yes, how?
Do they keep or lose 
their original 
properties?
Draw what the 
particles look like.

24. Identify the following with as many terms as apply
Table salt
Salad
Mayonnaise
Italian dressing
Pepsi
Oxygen
Hydrogen
Water
Mixture
Element
Compound
Homogeneous
Heterogeneous

25. MARSHMALLOW ACTIVITY