Answer:
Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. ... An example of a chemical change is the reaction between sodium and water to produce sodium hydroxide and hydrogen.
Step-by-step explanation:
The five basic types of chemical reactions are combination, decomposition, single-replacement, double-replacement, and combustion. Analyzing the reactants and products of a given reaction will allow you to place it into one of these categories.