General Chemistry 1411.115
Lab Partners: Kyle Winfield, Joey Balaszi, Connor Borman
October 26 2014
Experiment 7
INVESTIGATING STOICHIOMETRY WITH SODIUM SALTS OF CARBONIC ACID
Intro
The purpose of this experiment was to investigate chemical stoichiometry. The experiment conducted of combining sodium bicarbonate (NaHCO3) and sodium carbonate (Na2CO3) with hydrochloric acid (HCl) to produce sodium chloride, water and carbon dioxide. Balanced chemical reaction of HCl with sodium bicarbonate. NaHCO3 + HCl = NaCl + H2O + CO2
Theoretical Chemical reactions of NaHCO3 and Na2CO3 with HCl.
When hydrochloric acid reacts with either NaHCO3 or Na2CO3, it produces three products; sodium chloride, carbon dioxide, and water.
NaHCO3(s) + HCl(aq) NaCl(s) + CO2(g) H2O(l)
Na2CO3(s) + 2HCl(aq) 2NaCl(s) + CO2(g) + H2O(l)
Procedures used for both sodium carbonate and sodium bicarbonate
1. Find the mass of the 150mL beaker.
2. Weigh 0.15g of the unknown solution and place it into the beaker.
3. Add 50mL of distilled water into the beaker and Stir the beaker until the solution has dissolved.
4. Add 4-5 drops of bromocresol into the beaker and mix.
5. Place 50 mL of HCl in the burette.
6. Titrate by slowly dripping the 50 mL of HCl into the solution until a light green color appears.
7. Heat the titrated solution, a color change from green to blue should occur.
8. Titrate again, yellow color should occur.
9. Boil the substance to evaporate the H2O.
10. Weigh the flask with the remaining NaCl to find the weight.
Results:
Unknown #1
Trials
Beaker Mass (g)
Beaker + Unknown Mass (g)
Beaker + NaCl Mass (g)
1
115.0157
115.1956
115.066
2
105.724
105.875
106.0001
Unknown #2
Trials
Beaker