1. 4.2 Synthesis and Decomposition Reactions

2. Synthesis Reactions
Involves smaller atoms or molecules combining to form a larger molecule
Two or more reactants combine to make one product
element + element → compound
Synthesis reactions of non-metals create molecular compounds
Synthesis reactions can involve compounds coming together
compound + compound → new compound

3. General Equation

4. Synthesis Reactions involving Hydrogen
Usually forms a molecular compound

5. Example
Ex. 1) Hydrogen + oxygen → water

6. Synthesis Reactions Involving Other Reactions
Can be more difficult to predict
In these cases, the only way to identify the reaction products is by conducting chemical tests.

7. Examples Sodium + chlorine → sodium chloride
3 )Copper + Oxygen → copper (ll) oxide

8. Synthesis Involving Compounds
This is an important reaction that impacts aquatic ecosystems.

9. Decomposition Reaction
Opposite to synthesis
Involves a large molecule splitting to form smaller molecules or elements
One reactant breaks apart into two or more products
The general equation for a decomposition reaction is:
compound → element + element

10. Examples! 1) Water → Hydrogen + Oxygen
2) Triiodine mononitride→ Nitrogen + Iodine