Chemical Reactions

By: Paul Treible, Page 10

Schemes

Combination

Scheme: A+B ~> A=B

Ex: 3Mg +N2 = Mg3 N2

Decompostion

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

Combustion

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.