Synthesis Reactions : Simple substances combines to for a complex substance
Example: H2 + N2 --> NH3 Balanced: 3H2 + N2 = 2NH3
Example : H2 + O2 --> H2O Balanced: 2H2 + O2 = 2H2O
Decomposition Reactions: A complex substance breaks down to its simpler parts
Example: NH3 --> N2 + H2 Balanced: 2NH3 = N2 + 3H2
H2O --> O2 + H2 Balanced: 2H2O = O2 + 2H2
Single Replacement Reactions: One type of atom or group in a compund is replaced by another type of atom or group forming a new compund. Below --> Hydrogen in HCl is replaced by Aluminium in AlCl3
Example: Al + HCl --> AlCl3 + H2 Balanced : 2Al + 6HCl = 2AlCl3 + 3H2
Double Replacement Reactions : Two types of atoms or groups exchange places to form two new compunds.
Example: HCl + NaOH --> NaCl + H2O
Note: If you use CHEMIX School for balancing chemical
you must replace the arrow '-->' by '>' (greater then).
CHEMIX School example - Balancing chemical reactions : Al + HCl > AlCl3 + H2
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