Reações Químicas

A chemical reaction is a process by which a molecule or compound changes into different ones. That is the chemical bonds between atoms in the starting material. The reactants are broken and new bonds are formed in what's generated, the products.

Some reactions, like the combustion of organic fuels, are unidirectional. They're irreversible, and will continue until the reactants are completely used up, to form Carbon Dioxide and water. These stable products do not react with one and other to regenerate the reactants.

Other reactions, like the formation of Ammonia gas, are bidirectional, they're reversible, where the product molecules react with each other to regenerate the reactants, Nitrogen and Hydrogen gas. These reactions take place simultaneously and achieve equilibrium when the concentration of reactants and products equalize. For all chemical reactions, the number of atoms of each element in reactant molecules, are preserved.

Balanced within the products that they generate. For example, one molecule of Nitrogen gas reacts with three molecules of Hydrogen gas to yield two molecules of Ammonia. Thus incorporating the two Nitrogen's, and six Hydrogen's in total.