Download Physical Properties Physical Changes Chemical

Physical Properties
Physical Changes
Chemical Properties
Chemical Changes
Physical Properties
• Can be observed without changing the
identity of the matter.
Physical
Properties
What are some
physical
properties?
• color
• melting and
boiling point
• odor
Physical Changes
• Alters the form or appearance of a
material but does not convert the
material into new substance.
Physical Changes
– can be observed
without changing the
identity of the
substance
Some physical changes
would be
• boiling of a liquid
• melting of a solid
• dissolving a solid in a
liquid to give a
homogeneous mixture
— a SOLUTION.
Chemical Properties
• Is a property of matter that describes a
substance based on its ability to change
into a new substance.
• This property becomes apparent during a
chemical reaction, and can only be
observed by changing a substance's
chemical identity.
Examples of Chemical Properties
• Reactivity
• Flammability (the ability to catch on fire)
• Toxicity (the ability to be poisonous),
• Oxidation (the ability to react with oxygen,
which causes apple slices to turn brown
and iron to rust),
• Sensitivity to light
Chemical Changes
• A change in matter that forms one or
more new substances with different
properties.
Oxygen is highly reactive and can
combine with almost any element.
Hydrogen
Hydrogen is highly flammabl
Oxygen
Hydrogen and Oxygen are both
gasses.
The reactants H2 and 02
H
H
O
H
H
O
Combine to form H2O
H
H
H
H
The ProductsEnergy
O
O
Water has completely different
properties than the reactants that
make it up.
Hydrogen
Oxygen
Water
Physical property or chemical
Property?
• When considering properties to help
decide ask yourself “does observing the
property cause a new substance to
form?”.
Signs of a Chemical Change
• Heat (Exothermic)
• Cooling (Endothermic)
• Bubbles
• Light
• Precipitation
• Color change
Physical vs. Chemical
• Examples:
– melting point
physical
– flammable
chemical
– density
physical
– magnetic
physical
– tarnishes in air
chemical
Chemical or Physical Change