1. Chemical Reactions
Chemical Rxn- one or more substances is transformed into another substance
Evidence of a chemical rxn
Change in color
Change in temperature (energy)
Light given off
Precipitate formation-solid forms
Bubbles-gas formed
**the only way to be sure a chemical reaction takes place, the physical properties of the product must be different from the reactants**

2. Chemical Reactions
Reactants must come in contact with each other for a reaction to take place.
Reactants LEFT SIDE  Products RIGHT SIDE
States of matter for both the reactants and products
(s)-solid
(l)- liquid
(g)-gas
(aq)- aqueous- (dissolved in water)
(cr)-crystalline
 yields or produces
 reaction goes both forward and reverse

3. Classifying types of Chemical Reactions
Combustion - oxidation reaction of an organic compound in which heat is released, involves oxygen to form oxides.
CH4(s) + O2(g)  CO2(g) + H2O(l) + energy
Methane combusts
Ex.
Butane combusts

4. Synthesis-
2 or more reactants joining together to make a larger molecule
Ex. A + B  AB
C + O2  CO2
Na + O2 
6 CO2 + H2O  C6H12O6 + 6O2

5. Decomposition
A reaction in which a larger molecule breaks down to form simpler compounds
Ex: AB A + B
2 H2O 
2 NaCHO3  Na2CO3 + H2O + CO2

6. Single replacement (displacement) reaction
-A reaction in which one atom replaces another-
Ex. AB + C  CB + A
Zn HCl 
CaCl2 + K 
KF + Na 
NaCl + F 
Activities Series p. 281 and 832
-order of reactivity- You have to look at this

7. Double replacement (displacement) reaction
-a reaction in which two atoms switch places with one another
Ex: AB + CD  AD + CB
Mg(OH)2(aq) HCl(aq) 
NaOH + BaCO3 