Page 19 - Science Course 3 (Book 2)
P. 19
Mo8-L2a: How to Recognize Chemical Reactions?
The only way to know if a chemical reaction has
occurred is to study the chemical properties of the
substances before and after the change.
Key Concept Notice that no new atoms are created in a chemical
reaction. The existing atoms rearrange and form new
How to Recognize Chemical Reactions? substances.
What are some signs that a chemical reaction
might have occurred?
What happens in a chemical reaction?
In a chemical reaction, atoms of elements or
compounds rearrange and form different elements
or compounds.
Atoms rearrange when chemical bonds between
atoms break.
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