Types of Chemical Reactions: Exchange and Reversible

In exchange reactions, two or more reactants exchange their atoms to form products.

These reactions involve both decomposition — breaking of bonds in the reactants, and synthesis — forming new bonds to create products.

For example, when a glucose molecule reacts with ATP, a phosphate group from ATP is transferred to the glucose, producing ADP and glucose 6-phosphate.

Most chemical reactions are reversible; the products can react to form the original reactants.

For instance, in blood, carbon dioxide and water react to form bicarbonate and hydrogen ions in a reversible reaction.

Here, the forward reaction, which forms the products, and the reverse reaction, which converts the products back to reactants, can achieve a state of equilibrium with no net change in the amounts of reactants and products.

In this case, the equilibrium between the two reactions helps maintain the blood pH.