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What are
Physical and Chemical Properties?
What are Physical and
Chemical Properties? Sounds like a complicated question! It's not if you break
it down. What are properties? Properties are attributes, qualities or
characteristics of something. Properties are used to identify elements.
Properties are the characteristics of a substance which distinguishes it from
another substance. In chemistry these properties are called Physical properties
and Chemical properties. Most common
substances exist as solids, liquids and gases which have diverse
physical and chemical properties. Matter can
undergo physical and chemical changes called
Phase Changes.
Physical and Chemical Properties
- States of Matter
Substances are classified based on physical states, often referred to as the
States of Matter. At room
temperature and pressure the common Physical States of elements are solids, gases or liquids.
Matter is classified first by its physical state as a solid, liquid, or gas.
Secondly, we classify matter by it chemical constitution as an element, a
compound, or a mixture.
Physical
and Chemical Properties - What are Physical Properties?
What are Physical
Properties?
Definition:
Physical properties are the characteristics can be observed
without changing the substance into another substance. Physical
properties of matter are usually those that can be observed using our senses.
The observations usually consist of some type of numerical measurement. Examples
of Physical properties include Color, Freezing point, Boiling point, Melting
point, Density and Smell.
Physical
and Chemical Properties - What are Chemical Properties?
What are Chemical
Properties?
Definition:
Chemical properties are the characteristics that determine how
it will react with other substances or change from one substance
to another. Chemical properties, or characteristics, which are exhibited as one
substance and then chemically transformed into another. Chemical properties are
only observable during a chemical reaction. Reactions and changes to substances
can be brought about by Burning, Rusting, Heating, Exploding and Tarnishing.
Physical and Chemical Properties
What are
Physical and Chemical Properties - Understanding increased
The more
Physical and Chemical Properties we can identify for a
substance, the better we know the nature of the substance.
Chemistry experiments can be used to illustrate the Physical and
Chemical properties of elements and compounds and to provide
examples of chemical change which can be explained by the
rearrangement of atoms. The Physical and Chemical Properties of
a substance enable chemists to understand how it will behave
under various conditions.
What are
Physical and Chemical Properties of Common Elements
The
following articles provide important facts and information about
the Physical and Chemical properties of common elements and
substances.
Examples of Physical Properties
Examples of
Physical properties are:
-
Color
(vividness of visual appearance)
-
Luster
(a shine or glow)
-
Hardness
(rigid and resistant to pressure)
-
Odor
(distinctive smell)
-
Luminescence (emitting light not caused by heat)
-
Conductivity (transmission of heat or electricity or sound)
-
Solubility (ability to be dissolved)
-
Malleability (capable of being shaped or bent)
-
Ductility (easily pulled or stretched into a thin wire)
-
Density
(the measure of the relative "heaviness" of objects with a constant
volume)
-
Viscosity (resistance to flow - stickiness)
-
Compressibility (made more compact)
-
Freezing
point (temperature below which a liquid turns into a solid)
-
Boiling
point (temperature at which the vapor pressure is large enough that
bubbles form inside the body of the liquid)
-
Melting
point (temperature at which the solid melts to become a liquid)
-
Crystalline structure (geometric pattern e.g. rectangular, hexagonal)
-
Allotropic - Allotropes are forms of an element with different physical
and chemical properties occurring in two or more crystalline forms in
the same physical state. The physical properties can vary widely with
the allotropic form. Example: Forms of Carbon are graphite and diamonds.
Diamond is highly transparent. Graphite is opaque and black
In a physical change, the substances are not altered chemically,
but merely changed to another phase (i.e. gas, liquid, solid) or separated
or combined.
Examples of Chemical Properties
Examples of
chemical properties are:
-
Flammability (the ability to catch on fire)
-
Toxicity
(the ability to be poisonous)
-
Radioactivity (giving off ionizing radiation)
-
Heat of
combustion (amount of heat released when the substance is completely
burned)
-
Reactivity with water (what happens when a substance reacts with water)
-
Reactivity with acids (what happens when a substance reacts with an
acid)
-
Oxidation (the combination of a substance with oxygen)
-
Corrosion (a corrosive substance that will destroy or irreversibly
damage another surface)
In a
chemical change, the substances are altered chemically and display different
physical and chemical properties after the change.
Physical and Chemical Properties
of Water
Water is unique because it
is the only natural substance that can exist in three states of matter -
solid, liquid, and gas - at the temperatures normally found on Earth. For more
facts and information see the article on
Water Properties. |