(Chapter
17.2)
Physical property—characteristics of a material which can be observed
without changing the identity of the substances in that material; examples
include color shape, size, melting point, and boiling point
· Appearance—physical description of a substance (color
shape, size)
· Behavior—how a substance acts (magnetism, viscosity,
ductility)
· 
Physical properties can be used to separate mixtures
Physical Change—Change in a substance’s size, shape, or state of matter
· substance does not change identity when it undergoes a
physical change
·
distillation is a
process for separating a mixture by evaporating a liquid and condensing its
vapor
Chemical Property—characteristics of a substance indicating that it can
change chemically; for example, flammability or light sensitivity
Chemical
Change—occurs when one substance
changes to another substance
· Some chemical changes cause a temperature change,
smell, or bubbles
· Some chemical changes occur slowly, such as the
formation of rust
·
Chemical changes
can be sued to separate substances such as metals from their ores
Weathering of the Earth’s surface involves both chemical and
physical changes
· Physical—big rocks split into smaller ones; streams
carry rock particles from one place to another
·
Chemical—occurs
when limestone changes to calcium hydrogen carbonate due to acid rain
Law of
Conservation of Mass—Mass of all
substances present before a chemical change equals the mass of all substances
after the change
