2.4 Types of Chemical Reactions

Synthesis

Synthesis reactions are also known as formation reactions.

Definition: A synthesis reaction is when two or more reactants (usually elements) join to form a compound.

• A + B --> AB where A and B represent elements

The elements may form ionic compounds, like these:

• Sodium metal and chlorine gas combine to form sodium chloride.

• Magnesium metal reacts with oxygen gas to form magnesium oxide.

Or the elements may form covalent compounds, like this:

• Nitrogen gas and oxygen gas join to form dinitrogen monoxide.