Lab 10: Mass-Mass Relationships Lab

Summary/Purpose: In all chemical equations, reactants and products must have an equivalent number of total atoms of each element, which satisfies the Law of Conservation of Mass. In this lab we demonstrate this law by reacting sodium hydrogen carbonate with hydrochloric acid. After which we compared the actual yield of its product, Sodium chloride, to its theoretical yield and found the percent yield. Overall, this experiment predominantly aids in the understanding of mass-mass conversions in chemical equations.

Questions 1-4: 

 The data attained in this lab is:


Which reactant is limiting? How do you know?
Sodium hydrogen carbonate is the limiting reagent because we had an ample, or excess, amount of hydrochloric acid that we kept introducing to sodium hydrogen carbonate until it was no longer fizzing.

Find the theoretical yield of NaCl based on your limiting reactant.

 To find the theoretical yield of NaCl, you apply the mass to mass relationship between sodium hydrogen carbonate and sodium chloride, which is as follows:

Find the mass for the remaining solid product after the evaporation of water based on your experimental data. 

Find the percent yield for this experiment for the solid product. 


Products after evaporation: 




Sources of possible error: 
When we washed the NaCl off the watch glass, we used the water from the sink instead of the bottle, which added too much water into the evaporating dish. Consequently, the evaporation of the water when on the hot plate took a significantly long time and may not have completely evaporated, leaving behind excess substances.

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