# >> College & Higher Education >> College

How to Reduce a Coefficient in Balancing Chemistry Equations

A chemical equation is essentially composed of two main parts: reactants and products. The reactants, on the left of the equation, are the initial molecules, or compounds, that will undergo a chemical reaction. The products, on the right, are the resulting molecules of the reaction. According to the law of conservation of mass, the number of individual atoms on the product and reactant side must be equal. To achieve a balanced equation, coefficients may be placed in front of the compounds to make each side equivalent. All coefficients must be represented in lowest common terms.

Instructions

- 1
  Balance the chemical equation. The moles of reactants should equal the moles of products and be represented as whole numbers. For example, this is an unbalanced and balanced equation for the combustion of methane:
  
  Unbalanced: CH4 + O2 -> CO2 + H2O
  
  Balanced: 2CH4 + 4O2 -> 2CO2 + 4H2O
- 2
  Determine whether the coefficients are in lowest common terms. The coefficients for the balanced combustion example are 2, 4, 2 and 4. The lowest common term, or multiple, of all four coefficients is 2.
- 3
  Divide every coefficient by the lowest common multiple. This results in a final balanced equation:
  
  CH4 + 2O2 -> CO2 + 2H2O
- 4
  Check that the number of reactants is still equal to the number of products. There are four oxygen atoms, four hydrogen atoms and one carbon atom on each side of the equation. Therefore, the equation is balanced.

Topics for a Presentation on Education

How to Cite APA With No Date