Organization of Matter
Unit 1
Dr. Gray
Chem 1
Classification of Matter
• Matter may be divided into Pure Substances
and Mixtures
• A mixture is two or more substances which
are PHYSICALLY combined.
• Mixtures may be heterogeneous or
homogenous.
Classification of Matter
• A heterogeneous mixtures has a varied
composition throughout. A good example of a
heterogeneous mixture are rocks.
• A homogenous mixture has uniform
composition throughout the sample.
Homogenous mixtures are also know as
solutions. They may be solids, liquids, or
gases.
Classification of Matter
• An example of a solid solution is brass. Brass
has a uniform appearance. Brass is made of
zinc and copper.
• In most homogenous solutions the solvent is
water-( solutions consist of a solvent and a
solute). Soda water is an example in which
carbon dioxide is physically mixed with water.
Classification of Matter
• Since mixtures (both homogenous and
heterogeneous are formed by physically
combining two or more substances-they are
also separated (broken up) by physical means
as well.
• Filtration-a process used to separate
components of a heterogeneous mixture
based on particle size.
Classification of Matter
• Distillation- a process of separating a
homogenous mixture. This method is used for
solid-liquid mixtures. This is based on boiling
away the liquid portion of the homogenous
mixture and leaving the solid portion behind.
Classification of matter
• Chromatography- this is another special type
of method for separating mixtures. This uses
the solubility of substances and how well a
substances adsorbs (sticks to) a surface.
• This method is used in separating mixtures of
a gas and a liquid.
Classification of Matter
• PURE SUBSTANCES:
• Elements and compounds
• An element is a pure substance that cannot be
broken into two or more pure substances.
• A compound is the chemical combination of
two or more elements.
Classification of Matter
• Compounds have elements which chemically
join together in a definite fixed proportion.
• EXAMPLE: Water- has a fixed composition of
11.19 percent hydrogen and 88.81 percent
oxygen.
• Because the composition of each element is
fixed, compounds are pure substances
Classification of Matter
• Elements, which are organized mainly based
on their chemical properties into the Periodic
Table of Elements, are also pure substances.
• Elements are represent by one or two letters.
The first letter is always capitalized (H, Ca, Be)
Any Questions?