Balancing reaction equations This sequence of slides includes two approaches to balancing reaction equations. Individual slides may be copied elsewhere or used as templates. 1 Using symbols and no text 2 Using text prompts to explain each step of the process click here click here To return to this page, click the button to the top right of any slide.

2 Mg + O2  MgO 2  Symbols Mg + O2

2 Al + I2  AlI3 3 1½ 2  Symbols Al + I2

Write a balanced equation sodium hydroxide is ionic: what are the formulae of its ions? sodium hydroxide is ionic: what are the formulae of its ions? Na+ and OH- sodium + water  sodium hydroxide + hydrogen It’s balanced! Check the equation is balanced: count the number of reactant and product elements Add numbers in front of the ringed formula so that the total number of reactant symbols = total number of product symbols Write the formula of each substance as it is ringed above Reactants: 2Na 4H 2O Products: 2Na 4H 2O 2 Na + H2O 2  NaOH 2 + H2

References First example, with symbols only: Frank Harriss of Malvern College Second example, with text prompts: Steve Lewis