Six Types of Reactions

• Understanding the 6 types of chemical reactions is the foundation of stoichiometry.
• Stoichiometry is a branch of chemistry that deals with the quantitative analysis of chemical reactions. 

The 6 types of reactions are:

1. Synthesis
2. Decomposition
3. Single Replacement
4. Double Replacement
5. Neutralization
6. Combustion

Synthesis A+B →AB

• Usually elements→compound
• Balanced synthesis reactions:

1. 2 Ag + S → Ag2S
2. 4 Fe + 3 O2 → 2 Fe2O3
3. N2 + 3 H2 → 2 NH3

Decomposition AB→ A+B

• Reverse of synthesis
• Assume the compounds decompose to elements during decomposition
• Balanced decomposition reactions:

1. 2H₂O  →    2H₂  +  O₂
2.  2NaCl →    2Na  +  Cl₂
3.  Mg₃N₂ → 3Mg + N₂

Single Replacement A+ BC → B + AC

• Balanced single replacement equations:

1. 2 AgNO3 + Cu → Cu(NO3)2 + 2 Ag 
2.  2 KI + Cl2 → 2 KCl + I2
3.  Cl₂ + 2NaBr → 2NaCl + Br₂

Double Replacement AB+CD → AD + BC

• Balanced double replacement equations:

1. AgNO3 + KCl → AgCl + KNO3
2.  HCl + NaOH → HOH + NaCl
3.  Fe₂O₃ + 6HCl → 2FeCl₃ + 3H₂O

Neutralization 

• Reaction between an acid and a base
• Always produce water
• Balanced neutralization reactions: 

1. H₂SO₄ + 2 NaOH →  Na₂SO₄ + 2 H₂O
2.  HCl + NaOH → NaCl + HOH

Combustion

• Reaction when all substances in a compound are combined with oxygen which then produces carbon dioxide and water.
• Balanced combustion reactions:

1.  C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O 
2.  2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O

-Benedict Suratos