balancing equations

When a chemical reaction occurs, it can be described by an equation. This shows the chemicals that react (called the reactants) on the left-hand side, and the chemicals that they produce (called the products) on the right-hand side. The chemicals can be represented by their names or by their chemical symbols.

Unlike mathematical equations, the two sides are separated by an arrow, that indicates that the reactants form the products and not the other way round.



In this tutorial you will see plenty of chemical equations, both using the names of the chemicals and also their symbols. There is also an exercise at the end if you want to try your hand at balancing chemical equations!



A large number of chemical equations are more complicated than the simple ones you will see in this section. They are reversible, which means that the reactants react together to form the products, but as soon as the products are formed, they start to react together to reform the reactants!

Reversible equations proceed in both directions at once, with reactants forming products and products forming reactants simultaneously. Eventually, the system settles down and a balance (an equilibrium) is reached, with the reactants and products present in stable concentrations. This does not mean that the reaction stops, merely that it proceeds in both directions at the same rate, so that the concentrations do not change.