Decomposition of Sodium Bicarbonate Stoichiometry Lab
OBJECTIVES
The purpose of this lab is to:
-Perform a decomposition reaction and measure the mass of the product(s) formed
-Using stoichiometry to determine which thermal decomposition reaction occurred during
the experiment
-Calculate the percent yield and error for your experiment.
BACKGROUND
The word stoichiometry originates from the Greek words stoicheion; meaning element and
metron; meaning measure. We use stoichiometry to describe the relationship between the
relative quantities of substances taking part in a reaction or forming a compound, and are
typically a ratio of whole integers. In this lab, you will use stoichiometry to probe the
decomposition of sodium bicarbonate. Sodium bicarbonate may be more familiar to you as
baking soda. Baking soda is very commonly listed as an ingredient in recipes for baked goods,
pancakes and waffles. As the food item is being cooked or baked, the baking soda undergoes
decomposition, releasing gas and causing the food item to “rise” and have a “light” texture.
There are three theoretically possible chemical reactions that could occur during the thermal
decomposition of baking soda.
1) sodium bicarbonate (s) → sodium hydroxide (s) + carbon dioxide (g)
2) sodium bicarbonate (s) → sodium oxide (s) + carbon dioxide (g) + water (g)
3) sodium bicarbonate (s)→ sodium carbonate (s) + carbon dioxide (g) + water (g)
By comparing the theoretical yields of the possible solid products with the actual experimental
yield of the product, you will be able to determine which of the above decomposition reactions
occurred.
REQUIRED SUPPLIES
Sodium bicarbonate Bunsen Burner Crucible
Ceramic triangle Iron ring clamp Balance
Crucible tongs
