Balancing Equations Notes Copy everything in the red font

Chemical Reactions Reactants – the chemicals you start with Products – the chemicals that get created Conservation of Mass – matter cannot be created or destroyed All atoms that you start with must still exist after the reaction

Vinegar and Baking Soda Reaction

Burning a candle 2 C 20 H 42 (s) + 61 O 2 (g) = 40 CO 2 (g) + 42 H 2 O(g)

Using sugar and oxygen in your body for energy

Balancing Chemical Reaction Equations Draw boxes around the chemical formulas – never change them! Focus on one element at a time. How many of each element are in the products? Reactants? How can you change the number in front to make these match? Example: C 6 H 12 O 6 +O 2 →CO 2 +H 2 O

Move from left to right, balancing elements by changing the number in front of the boxes Repeat this until all elements are balanced Example: C 6 H 12 O 6 +6O 2 →6CO 2 +6H 2 O

Practice Problems 1. KClO 3  KCl + O 2 2. HgO  Hg + O 2