Types of reactions

2. 4 Types of chemical
reactions
-SYNTHESIS REACTION
-TWO OR MORE SUBSTANCES
COMBINE TO MAKE A MORE COMPLEX
SUBSTANCE
-example:
- 2H
2
+ O
2
→ 2H
2
O
Hint: End with fewer types
of molecules!

3. Decomposition Reaction:
-one substance is broken down into
two or more substances.
-The opposite of a synthesis
reaction!
-example:
2NaClO
3
→ 2NaCl + 3O
2
Hint! End with higher
number of molecules

4. - Electrolysis (running electric
current through materials) is
a method used to cause
decomposition reactions to
obtain pure substances.

6. Single replacement reaction
-an uncombined element takes the place of
an element that is part of a compound.
- example:
Zn + 2HCl → H
2
+ ZnCl
2

7. Zn + 2HCl → H
2
+ ZnCl
2
Zn+HCl
ReactantsProducts

8. Double replacement
reaction:
-different atoms in two different
compounds replace each other
(two compounds react to form two
new compounds).
-examples:
2KI + Pb(NO
3
)
2
→ 2KNO
3
+ PbI
2

10. Combustion Reactions
•Combine a fuel with oxygen to produce
water and carbon dioxide
•3 parts of this rxn are always the same!
•Only the fuel will change
•C
2
H
6
+ O
2
 H
2
O + CO
2
•CH
4
+ O
2
 H
2
O + CO
2
•C
3
H
8
+ O
2
 H
2
O + CO
2