Chemical Reactions

By: Paul Treible, Page 10



Scheme: A+B ~> A=B

Ex: 3Mg +N2 = Mg3 N2


Scheme: A=B ~> A+ B

Ex: Mg3 N2 ~> 3Mg+N2

Single Replacement

Scheme: A=B+C ~> A=C+B

Ex: 2KBr+Cl2 ~> 2KCl+Br2

Double Replacement

Scheme: A=B+C=D ~> A=C+B+D

Ex: NaOh+FeCl3~> FeOh+BaCl


Scheme: C#H#+O2 ~> CO2+ H2O

How to write and balance an equation

  1. Assemble correct formulas for all the reactants and products.
  2. Count the number of atoms of each type appearing on both sides.
  3. Balance the elements one at a time by adding coefficients.