What type of reaction involves the combination of molecules to form a more complex product?

The synthesis reaction is characterized by the combination of simpler reactants to form a more complex product. In this type of reaction, two or more substances, which may be elements or simpler compounds, react together to create a compound with a more complex structure. This process is fundamental in chemistry because it allows for the creation of various substances essential for both industrial processes and biological functions.

For instance, when two hydrogen atoms react with one oxygen atom, they synthesize water, H₂O, which is a more complex molecule compared to the simple diatomic gases. This type of reaction is commonly represented by the general equation: A + B → AB, where A and B are reactants and AB is the product.

Understanding synthesis reactions provides insight into how different chemical substances interact to produce new materials, which is a key concept in the study of chemistry.