Types of Reactions

Synthesis
A reaction that combines 2 or more reactants to form a product
Formula:

Ex. 2 Ag + S  Ag2S
      4 Fe + 3 O2  2 Fe2O3


Decomposition
A reaction that breaks down one reactant into 2 or more products
Formula:

Ex. 2 KClO3  2 KCl + 3 O2
Single Replacement (Displacement)
A reaction when one element replaces an ion in an ionic compound. Metal elements replace positive ions and non-metal elements replace negative ions.
Formula:
A + BC --> AC + B           (A = metal)
A + BC --> BA + C           (A = non-metal)
Ex. 2 AgNO3 + Cu  Cu(NO3)2 + 2 Ag
      2 KI + Cl2  2 KCl + I2


The element doing the replacing has to be higher on the Activity Series Chart than the one being replaced to have a reaction!!!!


PRACTICE:
Balance the equation and state what reaction it is.

N₂ + H₂ --> NH₃ 
C + Fe₂O₃ --> Fe + CO

NH₄I + Cl₂ --> NH₄Cl + I₂

Al + H₂SO₄ --> Al₂(SO₄)₃ + H₂

Au + HCl -->  ?

H₂O ---> ?

NaI + F₂ ---> ?