A chemical substance is a form of matter that has a definite chemical composition and characteristic properties. It cannot be separated into its constituent elements by physical separation methods alone. Chemical substances exist as solids, liquids, gases, or plasma and may change between these states. They can be combined or converted through chemical reactions to form other substances. A chemical substance may be a pure chemical element or compound. An element is made of a single type of atom and cannot be broken down further, while a compound is formed when two or more elements are chemically bonded together. There are millions of possible chemical compounds due to combinations of the known chemical elements. Chemists use chemical formulae and molecular structures to refer to compounds. Pure substances are often isolated

1. Chemical substance
Introduction and it's Properties

2. Introduction
• chemical substance is a form of matter having
constant chemical composition and characteristic
properties.
• chemical substance cannot be separated into its
constituent elements by physical separation methods,
i.e., without breaking chemical bonds.
• Chemical substances exist as solids, liquids, gases, or
plasma, and may change between these phases of
matter with changes in temperature or pressure.
Chemical substances may be combined or converted
to others by means of chemical reactions.

3. Definition
• Chemical substance can either be a pure
chemical element or a pure chemical compound.
But, there are exceptions to this definition; a pure
substance can also be defined as a form of matter
that has both definite composition and distinct
properties.
• Broader definitions of chemicals or chemical
substances can be found, for example: "the term
'chemical substance' means any organic or
inorganic substance of a particular molecular
identity, including – (i) any combination of such
substances occurring in whole or in part as a result

4. Chemical elements
• An element is a chemical substance made up
of a particular kind of atom and hence cannot
be broken down or transformed by a chemical
reaction into a different element, though it can
be transmuted into another element through a
nuclear reaction. This is so because all of the
atoms in a sample of an element have the same
number of protons, though they may be
different isotopes, with differing numbers of
neutrons.

5. Chemical compounds
• A chemical compound is a chemical substance that is
composed of a particular set of atoms or ions. Two or
more elements combined into one substance through a
chemical reaction form a chemical compound. All
compounds are substances, but not all substances are
compounds.
• A chemical compound can be either atoms bonded
together in molecules or crystals in which atoms,
molecules or ions form a crystalline lattice. Compounds
based primarily on carbon and hydrogen atoms are
called organic compounds, and all others are called
inorganic compounds. Compounds containing bonds
between carbon and a metal are called organometallic

6. Naming and indexing
• Chemists frequently refer to chemical compounds
using chemical formulae or molecular structure of the
compound. There has been a phenomenal growth in
the number of chemical compounds being synthesized
(or isolated), and then reported in the scientific
literature by professional chemists around the world.
•An enormous number of chemical compounds are
possible through the chemical combination of the
known chemical elements. As of May 2011, about sixty
million chemical compounds are known. The names of
many of these compounds are often nontrivial and
hence not very easy to remember or cite accurately.
Also it is difficult to keep the track of them in the

7. Isolation, purification, characterization, and
identification
• Often a pure substance needs to be isolated from a
mixture, for example from a natural source (where a
sample often contains numerous chemical
substances) or after a chemical reaction (which
often give mixtures of chemical substances).

8. Reference
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10. ~ "What is a chemical". Nicnas.gov.au. 2005-06-01.
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~ Joachim Schummer. "Coping with the Growth of
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