Reactions. CH.3 Balancing Reactions Reaction Types. A Chemical Reaction. Reactants Products Types of Chemical reactions: There are many types of reactions but most can be classified into a few simple reactions types. How do you know a chemical reaction has occurred? .
A balanced equation shows the relationship
between the quantities of all reactants and products.
Mg (s) + Cl2 (g) MgCl2 (s)
Here the oxidation number of Mg has changed from
zero to +2. Cl has changed from zero to -1.