Classify a reaction as combination, single replacement, double replacement, decomposition or combustion. Predict the products of combination and decomposition reactions. Use the activity series to predict products of single replacement reactions. Write the products of double replacement reactions using a solubility chart. Write the products for complete combustion reactions.
Chemical equations describe chemical reactions.
Equations must be balanced because of the law of conservation of mass. In a chemical reaction the ways in which atoms are joined are changed. Bonds are broken and new bonds are formed. The atoms are simply rearranged, not created or destroyed. In a balanced equation, each side of the equation has the same number of atoms of each element.