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. 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.

4. 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).

5. 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

6. 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.

7. 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.

8. 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

9. 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

10. 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.

11. 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.

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

13. 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.