irreversible
Some chemical reactions can occur in only one direction. These reactions are called irreversible reactions. The reactants can change to the products, but the products cannot change back to the reactants. These reactions are like making a cake. The ingredients of a cakesuch as eggs and flourare the reactants. They are mixed together and baked to form the cake, which is the product see Figure below . The cake cant be unbaked and unmixed to change it back to the raw eggs, flour, and other ingredients. So making a cake is irreversible.