1. Types of Reactions
Six Types

2. Single Replacement
A free element replaces one of the ions in a compound
A metal replaces a metal OR a nonmetal replaces a nonmetal
The single element replaces one of the ions in the solution and a new element appears from the ion in solution
Element + Compound yields element + compound

3. Examples
2 KI + Cl2 → 2 KCl + I2
2 AgNO3 + Cu → Cu(NO3)2 + 2 Ag

4. Double Replacement
The cations (+ ions) switch places OR anions (- ions) switch places
A metal replaces a metal AND a nonmetal replaces a nonmetal
Compound + Compound yields Compound + Compound

5. Double Replacement
Often one of the product will be a precipitate – an insoluble solid product that separates from a solution.

6. Examples AgNO3 + KCl → AgCl + KNO3
Barium chloride + potassium sulfate yields barium sulfate + potassium chloride
Make sure to switch the names and then write the formula accordingly, balancing charges
BaCl2 + K2SO4 → BaSO4 + 2 KCl

7. (Acid-Base) Neutralization
Special double displacement reaction
Acids: compounds that begin with hydrogen
Bases: compounds that end with hydroxide
Acid + hydroxide compound → Salt (ionic compound) + H2O

8. Example HCl + NaOH → NaCl + H2O H2SO4 + 2 NH4OH → (NH4)2SO4 + 2 H2O
NaCl is not the only salt!!!!
H2SO4 + 2 NH4OH → (NH4)2SO4 + 2 H2O

9. Synthesis
Two or more elements or compounds come together to make a single product
A + B → AB
Element or compound + element or compound yields a single compound

10. Examples
2 H2 + O2 → 2 H20
H20 + SO3 → H2SO4

11. Decomposition
A coming apart; a single reactant comes apart into 2 or more products
AB → A + B
Compound yields two or more smaller substances (elements and/or compounds)

12. Examples
2 KClO3 → 2 KCl + 3O2
2 HgO → 2 Hg + O2

13. Combustion (of hydrocarbon)
Hydrocarbon + oxygen → water + carbon dioxide
CxHy + O2 → H2O + CO2
Coefficients will change according to your hydrocarbon subscripts
C6H O2 → 6 H2O + 6 CO2

14. Many reactions will require activation energy
- energy required to start a reaction.
Some reactions need a catalyst
- a subst. which speeds up a reaction without being permanently changed itself.