Page 13 - Science Course 3 (Book 2)
P. 13
Mo8-L1b: How Do the Changes of Matter Affect Mass?
Most chemical changes cannot be reversed.
Some physical changes can be easily reversed, but
others cannot.
Mass of Wood Mass of Ashes, Carbon
and Oxygen Dioxide, and Water
Key Concept
How Do the Changes of Matter Affect Mass?
How do physical and chemical changes affect
mass?
Physical Chemical
Change Change
The law of conservation of mass states that the
total mass before a chemical reaction is the same as
the total mass after the chemical reaction.
Comparing Physical and Chemical Changes
Sometimes deciding if a change is physical or
chemical is easy, but often many factors must be
compared and considered.
Chemical changes produce a new substance, but
physical changes do not.
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