classification of matter

1. CLASSIFICATION OF
MATTER
VIJITHA V.
PHYSICAL SCIENCE
N.S.S.T.C PANDALAM
REG NO: 13304020

2. Elements, Compounds
and Mixtures
“ single, attached, play play…”

3. Introducing Little Miss
“Element”
Hi! I am Little Miss “Element”
I am PURE SUBSTANCE
I cannot be broken down into
any simpler substance by
means of a chemical reaction*
or electricity**!
*Chemical process refers to
chemical reaction or heat
**Electricity refers to
electrolysis

4. Elements
Definition of an element:
An element is a pure substance which
cannot be split up into two or more
simpler substances by chemical
means.
Sugar is not an element as it can be
broken down into carbon and water.

5. Elements
Note that an element:
• Consists of only one kind of atom,
• Cannot be broken down into a simpler
type of matter by either physical or
chemical means
• Can exist as either atoms (e.g. argon) or
molecules (e.g., nitrogen).

6. Examples of elements
Elements are made up of tiny particles
Elements can be further classified into two
groups:
Is the smallest particle
of an element and has
the same chemical properties
of the element
Is made up of two or more
atoms that are chemically
bonded together
(note: these atoms are of the
SAME element!!)
Hi, I am from the
“Noble gas” family
and I work alone
We
same
same!!

7. These are elements!
Atoms of same element
Cu
copper
element
Na
sodium
element
He
helium
element
Molecules of same element
H
Hydrogen
gas element
H
O
O O
ozone

8. Atoms
An element is made of tiny particles
called atoms.
The atoms of an element is different
from that of another element.

9. What is an atom?
Examples of models of
atoms:
H Na Cl
Hydrogen
atom
Sodium
atom
Chlorine
atom

10. Molecules
Very few elements exists as
atoms besides elements such
as helium and neon.
Most elements exist as
molecules.
For example, hydrogen
is H2.
Ozone is O3.

11. Hydrogen (H2) is a
diatomic molecule.
Ozone (O3) is a
triatomic molecule.
Molecules consisting of a
few atoms are called
polyatomic molecules.

12. Examples of molecules
(elements)
H H
N N
O
O
O
O O S
S S
S S
S
S
S

13. Chemical Symbols of Elements
Chemists use symbols to represent elements.
For example, O represents oxygen while Fe
represents iron.
Element Symbol Element Symbol
Calcium Ca Mercury Hg
Carbon C Neon Ne
Hydrogen H Silicon Si
Iron Fe Sodium Na

14. Introducing Little Miss
“Compounds”
Harlow! Hehee!!!
*giggles*
I am also a PURE SUBSTANCE
I am made up of a fixed number
of two or more elements
chemically combined.

15. Compounds
Note that a compound:
• can be broken down into a simpler type of
matter (elements) by chemical means (but
not by physical means),
• has properties that are different from its
component elements, and
• always contains the same ratio of its
component atoms.

16. What is a compound?
A compound is a substance which is made up of two or
more elements chemically combined together.
- Chemical reactions taking place.
Qn: Is this a compound?
It only contains one type
of element.
Qn: Is this a compound?
It only contains one type
of element.
Qn: Is this a compound?
O
H
H
O
O
It is not chemically
combined.

17. So, what is a compound
then?
H
Water Ammonia gas
Consists of two or more elements
And
They are chemically combined together!

18. Making compounds from their
elements Example: Making water (picture)
ELEMENTS
hydrogen COMPOUND
(colourless
gas)
oxygen
(colourless
gas)
lighted
splint
heat, light
and
explosion
water
(colourless liquid)
Water
Oxygen molecule
molecule
Hydrogen
molecule
mixture of
hydrogen
and
oxygen
water
Example: Making water (models)
heat,
light and
explosio
n

19. Making compounds from their
elements
Example: Making iron sulphide compound
elements compound
heat
Iron + sulphur  iron sulphide
+
yellow grey

heat
black

20. Summarizing
• A compound is made up of two or more
elements chemically joined together
• A compound has a fixed composition
• Every compound has a unique chemical
formula
• A compound has a completely different
properties from its elements
• A chemical reaction (decomposition or
electrolysis) is needed to separate the
elements in the compound

21. Think about this…
ROJAK!!

22. Introducing Little Mr. “Mixture”
Burp!!!! I am messy!
I am formed when two or more substances
joined together physically (without chemical
bonds)
I have the same properties as all the
substances
AIR
I am his best
friend!

23. Mixtures
Definition of a mixture:
A mixture is not a pure substance as it
contains a mixture of atoms of
molecules which are not chemically
combined together.

24. Mixtures
• Note that a mixture:
• consists of two or more different elements
and/or compounds NOT chemically combined.
• Can be homogeneous or non-homogeneous
• can be separated into its components by
physical means, and
• often retains many of the properties of its
components.

25. Mixtures
• Examples of mixtures include muddy
water and air.
Air is made up of gases such as nitrogen
and oxygen mixed together.

26. Little Mr “Mixture”
I do not have a fixed composition
of the substances.
A Mixture can be:
• element + element
• element + compound
• compound + compound
(Refer to page 59, Fig 4.7)
He is a “boo-boo!”
He can be separated to its
substances by physical
methods

27. Conclusion
An element is a pure substance which cannot be
split up into two or more simpler substances
by chemical means.
A compound consist of a fixed number of
different kinds of atoms chemically combined
together.
A mixture is not a pure substance as it contains
a mixture of atoms of molecules which are not
chemically combined together.

28. The End……