Ever needed to balance a chemical equation but it is too difficult to do it by hand? This application will help you to balance the equation in the blink of an eye. You just need to type the reactants and the products and click the button 'balance'. Sample Equations. Fe + Cl2 = FeCl3. KMnO4 + HCl = KCl + MnCl2 + H2O + Cl2. C6h5cooh + o2 = co2 + h2o. H3PO4 + Ca 2 = CaHPO4.